Histone Deacetylases Inhibitors

ABSTRACT

New inhibitors of histone deacetylases having antitumor activity, and the process of preparation thereof are herein described. These compounds belong to the structural formula (I)  
                 
 
where R 1  is a linear or branched chain containing at least two conjugated double bonds, A is an optionally substituted phenyl or pyridyl ring, Ar is an aryl or heteroaryl group, and R 3  is hydrogen or alkoxyalkyl. The application also describes the use of said compounds in the treatment of diseases associated to the deregulation of histone deacetylases activity, such as tumors, as well as the relevant pharmaceutical compositions for administration to patients requiring said treatment.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is entitled to the benefit of and incorporates byreference essential subject matter disclosed in International PatentApplication No. PCT/EP2005/054949 filed on Sep. 30, 2005 and ItalianPatent Application No. MI2004A001869 filed Oct. 1, 2004.

FIELD OF THE INVENTION

The present invention relates to the field of antitumor compounds. Newinhibitors of histone deacetylases with cinnamoylamidic structure areherein described, useful in the treatment of diseases linked to thederegulation of histone deacetylases activity, such as in antitumortherapy.

BACKGROUND OF THE INVENTION

The reversible histone acetylation taking place on the ε-amino group ofthe lysine residue in the histone N-terminal section mediates importantconformational modifications within the nucleosomes. These modificationsaffect DNA capability to access transcription factors as well as genicexpression (Curr. Opin. Genet. Dev. 1998, 8, 173-178). Two classes ofenzymes are involved in histone acetylation: histone acetyltransferases(HATs), which catalyse histone acetylation by acting as transcriptionco-activators, and histone deacetylases (HDACs); the latter enzymes arerecruited at the level of promoter regions by transcription repressorsand co-repressors such as Sin3, SMRT, and N-CoR, leading to theformation of hypoacetylated histones and transcription silencing (TrendsBiochem. Sci. 2000, 25, 619-623). The aberrant recruitment of histonedeacetylases through oncogenic proteins, or the disturbed balance ofactivities of histone acetyltransferases and histone deacetylases innormal cells are involved in a number of pathologies:

first of all, in tumor diseases (Oncogene 2001, 20, 7204-7215,7186-7203, 3116-3127; Nature 1998, 391, 815-818; Mol. Cell. Biol. 1998,18, 7176-7184).

in several non-tumor diseases:

Nervous System:

Huntington's disease (J Neurosci 23, 9418-27 (2003); Proc Natl Acad SciUSA 100, 2041-6 (2003)), diseases caused by triplette amplifications(Curr Med Chem 10, 2577-87 (2003); Curr Biol 12, R141-3 (2002)),neuroprotection against degenerative diseases (FEBS Lett 542, 74-8(2003); ischemia (J Neurochem 89, 1358-67 (2004)), oxidative stress(Proc Natl Acad Sci USA 100, 4281-6 (2003)), inflammatory responses ofthe nervous system (J Neurochem 87, 407-16 (2003)), epilepsy (Epilepsia45, 737-44 (2004), J Neurosci 22, 8422-8 (2002)), diseases caused byprotein aggregates (Curr Biol 14, 488-92 (2004)).

Infection:

HIV (Mol Cell Biol 23, 6200-9 (2003), Embo J 15, 1112-20 (1996), BiochemPharmacol 68, 1231-8 2004), Aids 18, 1101-8 (2004)), malaria,leishmaniosis, infections caused by protozoa, fungi, phytotoxic agents,virus, parasites.

Immune System:

autoimmune diseases (Blood 101, 1430-8 (2003)), chronic host-directedimmune reaction (Proc Nat Acad Sci USA 101, 3921-6 (2004)).

Heart:

hypertrophy and cardiac disorders (J Clin Invest 112, 863-71 (2003),Novartis Found Symp 259, 132-41, discussion 141-5, 163-9 (2004), J ClinInvest 112, 824-6 (2003)).

Muscular Apparatus:

skin fibrotic disease (Exp Cell Res 278, 184-97 (2002)), fibrosis(Hepatology 29, 858-67 (1999)), spinal and bulbar muscular atrophy, (HumMol Genet. 13, 1183-92 (2004)).

Psychic System:

bipolar disorders (Nature 417, 292-5 (2002)), psychiatric disorders(Crit. Rev Neurobiol 15, 121-42 (2003)), X-fragile syndrome (BMC MolBiol 4, 3 (2003), Hum Mol Genet. 8, 2317-23 (1999)).

Others:

arthritis (Mol Ther 8, 707-17 (2003)), renal diseases (J Clin Invest111, 539-52 (2003)), psoriasis (Curr Drug Targets Inflamm Allergy 3,213-9 (2004)), intestinal diseases, colitis (Wien Klin Wochenschr 114,289-300 (2002)), beta thalassemy (Expert Opin Investig Drugs 10, 925-34(2001)), respiratory diseases (Am J Respir Crit. Care Med 167, 813-8(2003)), Rubinstein-Taybi syndrome (Neuron 42, 947-59 (2004)).

Histone deacetylases inhibitors, such as the natural productstricostatin A (TSA), trapoxin (TPX), and depsipeptide FK-228, shortchain fatty acids, sodium butyrrate, phenylbutyrrate and valproate,hydroxamic acid, hydroxamates such as the suberoylanilide hydroxamicacid (SAHA), pyroxamide, scriptaid, oxamflatin, NVP-LAQ824, cyclicpeptides containing hydroxamic acid (CHAPs), and the benzamide MS-275strongly promote growth interruption, differentiation and apoptosis in anumber of transformed cells in culture and in animal models (Curr. Opin.Oncol. 2001, 13, 477-483). Among them, sodium phenylbutyrate (alone orin combination), depsipeptide, SAHA, pyroxamide, NVP-LAQ824, MS-275, arein clinical phase I and/or II for the treatment of several cancerousdiseases (Nat. Rev. Drug Discov. 2002, 1, 287-299). Nevertheless theirclinical utility is restricted by toxicity problems (TSA, CHAPs,MS-275), low stability (TSA, trapoxin), low solubility (TSA), lowpotency and lack of selectivity (butyrates and analogues) (Anti-CancerDrugs 2001, 13, 1-13).

WO 04/063169 discloses hydroxamic acid derivatives as HDAC inhibitorswith the following general formula:

with R¹ is a N-containing heterocyclic ring optionally substituted withone or more suitable groups, R² is hydroxylamino, R³ is hydrogen or asuitable substituent, L¹ is —(CH₂)_(n)— with n an integer of 0 to 6,optionally substituted with one or more suitable substitutents andwherein one or more methylene(s) may be replaced with suitableheteroatom(s); L² is a lower alkylene chain.

WO 03/087066 describes hydroxamic acid derivatives and their use ashistone deacetylase inhibitors with the following formula

where A is an optionally substituted phenyl or aromatic heterocyclicgroup; m and n independently an integer from 0 to 4; and X is a moietyhaving a structure selected from

where R2 is hydrogen or optionally substituted C₁-C₄ alkyl.

WO 02/22577 discloses the following hydroxamic acid derivatives asdeacetylase inhibitors of general formula

where R¹ is hydrogen, halogen or a C₁-C₆ alkyl chain, R₂ is selectedfrom H, C₁-C₁₀ alkyl, C₄-C₉ cycloalkyl, C₄-C₉ heterocycloalkyl,cycloalkylalkyl, aryl, heteroaryl etc.; R₃ and R₄ are independentlyselected from hydrogen, C₁-C₆ alkyl, acyl or acylaminoR₅ is selected from hydrogen, C₁-C₆ alkyl and others; n₁, n₂ and n₃ arean integer from 0 to 6, X and Y are selected from hydrogen, halogen,C₁-C₄ alkyl etc.

WO 01/38322 describes histone deacetylase inhibitors of the generalformulaCy-L¹-Ar—Y¹—C(O)—NH-Zwhere Cy is an optionally substituted cycloalkyl, aryl, heteroaryl orheterocyclyl ring; L¹ is —(CH₂)_(m)—W with m an integer from 0 to 4, Wis selected among others from C(O)NH—, S(O)₂—NH—; Ar is an optionallysubstituted arylene ring, wherein said arylene may be optionally fusedto an aryl or heteroaryl ring, Y¹ is a bond or a saturated alkylenechain; Z is among other groups O-M, wherein M is hydrogen or a suitablepharmaceutical cation ion.

WO 95/13264 discloses hydroxamic acid derivatives of general formula

wherein R¹ represents among other groups phenyl or aryloxyphenyl; L isC₁-C₈ alkylene, C₂-C₈ alkenylene, (CH₂)_(m)—O— (wherein m is an integerfrom 0 to 4), or —CO—; n is 0 or 1; R² is hydrogen, C₁-C₄ alkyl orarylalkyl; M is, hydrogen, alkoyl, alkoxycarbonyl; and their use asmedicinal having the effect of suppressing smooth muscle growth andbeing usable as a vascular wall thickening preventive, a post-PTCAretenosis preventive and even an antiarterosclerotic agent.

Mai et al. describe in J. Med. Chem. 2001, 44, 2069-2072, J. Med. Chem.2002, 45, 1778-1784, J. Med. Chem. 2003, 46, 512-524, J. Med. Chem.2003, 46, 4826-4829, J. Med. Chem. 2004, 47, 1098-1109, J. Med. Chem.2004, 47, 1351-1359 and J. Med. Chem. 2005, 48, 3344-3353 pyrrolylhydroxamide derivatives as selective HDAC inhibitors.

Further HDAC inhibitors are discussed in Expert Opin. Ther. Patents2004, 14(6), 791-804). Histone deacetylases inhibitors were alsoidentified with different affinities with respect to specific subclassesof histone deacetylases (HD2, HD1-A, HD1-B): the discriminating abilityamong the various subclasses of histone deacetylases leads to importantconsequences: i.e. the elimination of side effects and/or the activitytowards specific forms of tumor.

However, none of the aforementioned compounds has so far shown a fullysatisfactory profile. It is thus still desired to find new histonedeacetylases inhibitors having useful antitumor properties, adequateselectivity and stability of action; also, the search is open for newinhibitors having high activity on histone deacetylases, possiblyshowing a higher activity with respect to specific subclasses thereof.

BRIEF SUMMARY OF THE INVENTION

We have now found a new group of histone deacetylase inhibitors withhigh and stable antitumor activity. These inhibitors are described bythe following general formula (I)

wherein:R₁ is a linear or branched chain, containing at least two conjugateddouble bonds,R₃ is chosen among hydrogen, alkoxyalkyl;Ar is an optionally substituted aryl or heteroaryl group.A is chosen among:

wherein R₂ is chosen among hydrogen, alkyl, cycloalkyl, aryl, arylalkyl,heterocyclyl, heterocyclylalkyl, halogen, haloalkyl, hydroxy,hydroxyalkyl, alkoxy, haloalkoxy, amino, aminoalkyl, alkylamino,(thio)carbonylamino, (thio)aminocarbonil, sulphonylamino,aminosulphonyl, (thio)acyl, (thio)acyloxy, (thio)alkoxycarbonyl, nitroand nitryl;

The compounds of formula (I) can be synthesised by treating a compoundof formula (II) where A and R₂ have the aforesaid meanings and R₄ is asuitable leaving group, for example a halogen like bromine or iodine:

(i) with a compound of formula Ar—W, where Ar has the aforesaidmeanings, and W is a group capable to form, by reaction with the CHOgroup of (II), the group R¹, as defined above, or a synthesisintermediate thereof,(ii) and further with a compound of formula (III)

where Z represents the group NHOR₃ as defined above or a precursorthereof, and where the steps (i) and (ii) may take place in any order.

The compounds of formula (I) are strong inhibitors of histonedeacetylases, with IC₅₀ in the order of 1 μM or lower. These compoundspresent broad spectrum and stable activity in the course of time: bothfeatures are ideal from the point of view of therapeutic application.Furthermore, the compounds of formula (I) strongly promote apoptosis andinhibit cell proliferation on a panel of tumor cells.

The invention includes the use of the compounds of formula (I) in thetreatment and/or prevention of diseases associated with the deregulationof histone deacetylases activities and the relevant pharmaceuticalcompositions for administration of said compounds.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a result of the treatment of U937 cells with the compoundsindicated (200 nM, 1 μM) for 4 h and 24 h.

FIG. 2 is a Treatment of U937 cells with the compounds of the invention:effect on cell growth and apoptosis.

FIG. 3 is a Treatment of K562 and HT29 cells with the compounds of theinvention: Effects on cell cycle, cell growth and apoptosis.

FIG. 4 is an Effect of the new HDACi administration on normal cutis(immunohistochemistry for detection of acetylated histones).

FIG. 5 is an Effect of the new HDACi administration on cutis afterinduction and occurrence of papillomas (histochemistry for detection ofacetylated histones).

FIG. 6 is an Effect of treatments with the new HDACi on the number ofpapillomas.

DETAILED DESCRIPTION OF THE INVENTION

In the aforementioned formula (I) the alkyl groups, either alone orcomprised within higher structures (e.g. alkoxy, arylalkyl, etc.),contain preferably from 1 to 8, (more preferably from 1 to 4) carbonatoms and can be linear or branched, and possibly substituted.

The acyl groups, either alone or comprised within higher structures(e.g. acyloxy), preferably contain from 1 to 8, more preferably from 1to 4 carbon atoms and can be linear or branched, saturated orunsaturated, and possibly substituted.

The cycloalkyl group preferably contain from 3 to 8, more preferablyfrom 3 to 6 carbon atoms and can be saturated or unsaturated, andpossibly substituted.

The aryl groups, either alone or comprised within higher structures(e.g. arylalkyl), are aromatic monocyclic or polycyclic rings,preferably containing from 6 to 10 carbon atoms per ring, possiblysubstituted; a preferred example of aryl is the phenyl group.

Heterocyclyl groups, either alone or comprised within higher structures(e.g. heterocycloalkyl), either monocyclic or polycyclic, containpreferably from 4 to 8 members per ring, 1 to 3 members or them beingheteroatoms such as N, O, S, and can be saturated or unsaturated andpossibly substituted.

In all said possibly substituted groups, the possible substituents canbe chosen e.g. among the hydroxy, alkoxy, haloalkoxy, amino,aminocarbonyl, carbonylamino, carbonylamide, amide, carboxyl,alkoxycarbonyl, aminoalkyl, alkylamino, dialkylamino, pyridyl,piperazinyl, morpholyl, halogen, nitro and nitryl function.

To the aforesaid definition of R₁ belong any α,β unsaturated functions,including those wherein the α,β unsaturation involves non-carbon atoms,e.g. oxygen, nitrogen, or sulphur atoms. Thus R1 may be a carbon atomchain, or a ═Y substituted carbon atom chain wherein Y represents thenon-carbon atom involved in the α,β unsaturation. Preferably R1 includesfrom 3 to 8 carbon atoms; morepreferably, R₁ is chosen among the following structures:

wherein Y is chosen among O, S, NH, CH₂, NOH or NOR₅ with R₅ alkyl from1 to 4 carbon atoms,

Preferred meanings for the Ar group are: phenyl, naphtyl, pyridyl,pyranyl, pyrrolyl, thienyl, furanyl, benzofuryl, benzothienyl, indolyl.

Whenever present, the optional substituent of the Ar group is preferablychosen among halogen, hydroxy, alkyl, alkoxy, trifluoroalkyl,trifluoroalkoxy, dialkylamino, morpholyl, piperazinyl, metoxycarbonyl.

The connections of the A ring to R₁ and to the R₃-containing residue arepreferably in para relationship to each other on the A ring. The R₂substituent may be attached at any available position of the A ring;preferred meanings for R₂ are hydrogen, halogen, alkyl, alkoxy.Preferred meaning for R₃ is hydrogen.

Preferred substructures of formula (I) are the following formulas (Ia),(Ib), (Ic) and Id):

where Ar and R₂ have the aforesaid meanings, and X is a carbon ornitrogen atom.

The invention further includes a process for the preparation of thecompounds of formula (I). In its most general meaning the processincludes the treatment of a compound of formula (II)

where A and R₂ have the aforesaid meanings and R₄ is a suitable leavinggroup, e.g. a halogen such as bromine and iodine(i) with a compound of formula Ar—W, where Ar has the aforesaidmeanings, and W is a group capable to form, by reaction with the CHOgroup of (II), said R₁, group, or a synthetic intermediate thereof,(ii) and further with a compound of formula (III)

where Z represents NHOR₃ as defined above or a precursor thereof.

The addition reaction of compound Ar—W generally takes place in alkalineenvironment; preferably the compound Ar—W is an acetophenone optionallysubstituted on the phenyl ring.

Preferably the compound of formula (III) is an alkylacrylate, morepreferably a n-butyl acrylate. The addition of the compound of formula(III) generally takes place in the presence of potassium phosphate andpalladium acetate; in case of the alkylacrylates of formula (III) theO-alkyl group works as a precursor of the NHOH group; its conversion toNHOH takes place according to known techniques, as exemplified below.

In particular, the preferred compounds of formula (Ia) can be obtainedby deprotection of compounds of formula (IV) or (IVa) according to thefollowing synthetic route:

In all formulas herein presented, the ring marked with “Het” representsthe pyridine ring:

Protecting groups PG₁, chosen in accordance with normal chemicalpractice, are removed by standard methods. When PG₁ is atetrahydropyranyl or 2-methoxy-2-propyl residue, acidic conditions areused such as hydrochloric acid in aprotic solvents (e.g. diethyl ether,dioxane or THF).

Compounds of formula (IV) are obtained by reaction of compounds offormula (V) with protected hydroxylamine (NH₂OPG₁)

The coupling reaction may be promoted by coupling agents known in theart of organic synthesis such as EDC(1-(3-dimethylaminopropyl)-3-ethylcarbodiimide),DCC(N,N′-dicyclohexyl-carbodiimide) or by polymer-supported couplingagents such as polymer-supported carbodiimide (PS-DCC, ex ArgonautTechnologies), in the presence of a suitable base such as triethylamine,diisopropylethylamine, in a suitable solvent (e.g. tetrahydrofuran,dichloromethane, N,N-dimethylformamide).

Typically, a co-catalyst such as HOBT (1-hydroxy-benzotriazole), HOAT(1-hydroxy-7-azabenzotriazole) and the like may also be present in thereaction mixture. The reaction typically proceeds at room temperaturefor a time in the range of about 2 hours up to 12 hours.

Compounds of formula (V) can be obtained by reaction of compounds offormula (VI)

with compounds of formula (VII)

in presence of an inorganic base such as KOH or NaOH in protic solvent,such as ethanol, methanol or water. The reaction typically proceeds from0° C. to room temperature for a time in the range of about 2 hours up to12 hours.

The compounds of formula (VII) are known commercially availablecompounds or they can be prepared from known compounds by known methods,or methods analogous to those used to prepare known compounds.

The compounds of formula (VI) are commercially available or can beprepared by reaction of compounds of formula (VIII), whereas B ishalogen, in particular bromo or iodo,

with tert-butylacrylate using classical Heck reaction conditions asdescribed by Larhed, M.; Hallberg, A. in Handbook of OrganopalladiumChemistry for Organic Synthesis; Negishi, E., Ed.; Wiley-Interscience:New York, 2002. The reaction takes place in presence of palladium salts,such as palladium acetate, organic and inorganic bases (triethylamine,1,4-diazabicyclo[2.2.2]octane and sodium bicarbonate or potassiumbicarbonate) and, eventually, phosphine derivatives, such astriphenylphospine in DMF. The reaction typically proceeds from roomtemperature to reflux, usually at 100° C., for a time in the range ofabout 2 hours up to 12 hours. Suitable deprotection methods fortert-butyl ester conversion into the corresponding carboxylic acid willbe those used conventionally in the art with reference to standard textssuch as Greene, T. W. and Wuts, P. G. M. Protective Groups in OrganicSynthesis, John Wiley & Sons Inc. New York, 1991 (Second Edt.) or inKocienski, P. J. Protecting groups. George Thieme Verlag, New York,1994.

The compounds of formula (VIII) are known commercially availablecompounds or they can be prepared from known compounds by known methods,or methods analogous to those used to prepare known compounds.

Alternatively compounds of formula (V) can be obtained by reaction ofcompounds of formula (IX)

with compounds of formula (VII) in presence of an inorganic base such asKOH or NaOH in protic solvent, such as ethanol, methanol or water. Thereaction typically proceeds from 0° C. to room temperature for a time inthe range of about 2 hours up to 12 hours. Suitable deprotection methodsfor tert-butyl ester conversion into the corresponding carboxylic acidwill be those used conventionally in the art.

The compounds of formula (IX) can be prepared by reaction of compoundsof formula (VIII), whereas B is halogen in particular bromo or iodo,with tert-butylacrylate using classical Heck conditions similar to thosedescribed for the synthesis of compounds of formula (VI).

Alternatively compounds of formula (V) can be obtained by reaction ofcompounds of formula (X)

with tert-butyldiethylphosphonoacetate in presence of an inorganic basesuch as sodium hydride in aprotic solvent such as THF. The reactiontypically proceeds from 0° C. to room temperature for a time in therange of about 1 hour up to 12 hours. Suitable deprotection methods fortert-butyl ester conversion into the corresponding carboxylic acid willbe those used conventionally in the art.

Compounds of formula (X) can be prepared by reaction of compounds offormula (XI)

with compounds of formula (VII) in presence of an inorganic base such asKOH or NaOH in protic solvents such as ethanol, methanol or water. Thereaction typically proceeds from 0° C. to room temperature for a time inthe range of about 1 hour up to 12 hours. Suitable deprotection methodsfor dimethyl acetal conversion into the corresponding aldehyde will bethose used conventionally in the art with reference to standard textssuch as Greene, T. W. and Wuts, P. G. M. Protective Groups in OrganicSynthesis, John Wiley & Sons Inc. New York, 1991 (Second Edt.) or inKocienski, P. J. Protecting groups. George Thieme Verlag, New York,1994.

Compounds of formula (XI) can be prepared by reaction of compounds offormula (XII)

whereas B is Halogen, in Particular Bromo or Iodo, with an AlkylLithium, Such as n-butyl lithium, followed by addition of DMF in aproticsolvent such as THF. The reaction typically proceeds from −78° C. toroom temperature for a time in the range of about 1 hour up to 3 hours.

Compounds of formula (XII) can be obtained from compounds of formula(VIII) by conversion of aldehyde in the corresponding dimethyl acetateusing suitable protection methods that will be those used conventionallyin the art.

Alternatively compounds of formula (V) can be obtained by reaction ofcompounds of formula (XIII) whereas B is halogen, in particular bromo oriodo,

with tert-butylacrylate using classical Heck conditions similar to thosedescribed for the synthesis of compounds of formula (VI). Deprotectionof the tert-butyl ester is carried out according to the known standardprocedures.

Compounds of formula (XIII) can be prepared by reaction of compounds offormula (VIII) with compounds of formula (VII) in presence of an organicor inorganic base such as KOH or NaOH in protic solvent, such asethanol, methanol or water. The reaction typically proceeds from 0° C.to reflux, for a time in the range of about 1 hour to 36 hours.

When A is an heteroaryl, compounds of formula (IVa) are obtained byreaction of compounds of formula (XIV) with protected hydroxylamine(NH₂OPG₁).

The coupling reaction may be promoted by coupling agents known in theart of organic synthesis such as EDC(1-(3-dimethylaminopropyl)-3-ethylcarbodiimide),DCC(N,N′-dicyclohexyl-carbodiimide) or by polymer-supported couplingagents such as polymer-supported carbodiimide (PS-DCC, ex ArgonautTechnologies), in the presence of a suitable base such as triethylamine,diisopropylethylamine, in a suitable solvent (e.g. tetrahydrofuran,dichloromethane, N,N-dimethylformamide).

Typically, a co-catalyst such as HOBT (1-hydroxy-benzotriazole), HOAT(1-hydroxy-7-azabenzotriazole) and the like may also be present in thereaction mixture. The reaction typically proceeds at room temperaturefor a time in the range of about 2 hours up to 12 hours.

Compounds of formula (XIV) can be prepared by reaction of compounds offormula (XV)

with compounds of formula (VII) using the same experimental conditionsdescribed above. Deprotection of the tert-butyl ester is carried outaccording to the known standard procedures.

Compounds of formula (XV) can be prepared by reaction of compounds offormula (XVI)

with tert-butyldiethylphosphonoacetate in presence of inorganic basesuch as sodium hydride in aprotic solvent such as THF. The reactiontypically proceeds from 0° C. to room temperature for a time in therange of about 1 hour up to 12 hours. Suitable methods for conversion ofthe dimethyl acetal into the corresponding aldehyde will be those usedconventionally in the art.

Compounds of formula (XVI) can be prepared using the same proceduresdescribed for the synthesis of compounds of formula (XI).

The preferred compounds of formula (Ib) can be obtained according to thefollowing synthetic route:

Step a can be performed in presence of potassium phosphate and palladiumacetate. Step b can be performed by adding the suitable acetophenone ton-butyl-3-formylcinnamate, in alcoholic basic environment. Step c can beperformed by treating the carboxylic acid derivative in scheme 2 with aprotected hydroxylamine under standard peptidic coupling conditionsknown in the art. For compounds of formula (Ic) it is possible to usethe following synthetic route:

Steps a and c can be performed in alcoholic basic environment. Step bcan be performed in presence of potassium phosphate and palladiumacetate. Step d can be performed by reaction with ethyl chloroformiateand triethylamine, followed by treatment withO-(2-methoxy-2-propyl)hydroxylamine and elution on ion exchange resin.

The compounds of formula (Id) can be obtained by analogue reactions.

Due to the interposition of R₁ between the Ar- and cinnamoylamidegroups, the compounds of formula (I) are characterised by an extendedarea of electron conjugation: a special role is played by the centralaromatic or heteroaromatic group represented in formula (I) which, dueto its intrinsic aromatic character, allows an ideal degree of resonancealong the entire longitudinal axis of the molecule, stretching from Arto the NHOR₃ group.

All compounds of formula (I) are endowed with interestingpharmacological properties. In fact they show a high histonedeacetylases inhibiting activity, with IC₅₀ in the order of 1 μM orlower. Regarding a variety of cell lines, this activity is broadspectrum and is stable throughout the time: both features are ideal fromthe point of view of the therapeutic application. The compounds offormula (I) also show a powerful activity in promoting apoptosis andinhibiting cell proliferation in a panel of tumor cells, which furthersupports the antitumor efficacy.

The present invention includes the compounds of said formula (I), foruse in therapy, in particular in the treatment of diseases associated tohistone deacetylases deregulation.

Further object of the invention are pharmaceutical compositions fortreatment and prevention of diseases associated to deregulation ofhistone deacetylases activity, characterised by containing one or moreactive principles of formula (I), in association with pharmaceuticallyacceptable excipients and diluents.

The compounds of the invention have a synergistic action with knownantitumor drugs: the aforesaid pharmaceutical compositions can thusinclude further known antitumor agents and/or any further drug usefulfor co-administration with antitumor agents (ad. es. immunostimulatingcompounds, promoters of cell differentiation, etc.).

The compounds of this invention can be administered in conventionalmanner, e.g. orally, intravenously, subcutaneously, transmucosally(including buccally, sublingually, transurethrally, and rectally),topically, transdermally, by inhalation, or using any other route ofadministration.

The compounds of formula (I) can be formulated pharmaceuticallyaccording to known methods. The pharmaceutical compositions can bechosen in function of the treatment. Said compositions are prepared bysuitable mixing of their ingredients and are suitably adapted for oralor parenteral administration; they can be formulated as tablets,capsules, oral preparations, powders, granules, lozenges, regenerablepowders, liquid injectable or infusible solutions, suspensions orsuppositories.

Tablets and capsules for oral administration are normally presented asunitary dosage form, and may contain conventional excipients such asbinders, fillers, diluents, tabletting agents, lubricants, detergents,disintegrants, dyes, flavours and wetting agents. Tablets can be coatedaccording to methods well known in the art.

Suitable fillers include cellulose, mannitol, lactose and furthersimilar agents.

Suitable disintegrants include starch, polyvinylpyrrolidone and starchderivatives such as starch sodium glycolate. Suitable lubricantsinclude, e.g. magnesium stearate. Suitable wetting agents include sodiumlaurylsulphate.

Solid oral compositions can be prepared by conventional mixing, fillingor compression. It is possible to repeat the mixing operations in orderto disperse the active agent in compositions containing high amounts offillers. These operations are conventional.

Liquid oral preparations can be formulated e.g. as aqueous or oilysuspensions or solutions, emulsions, syrups or elixir, or can bepresented as freeze dried product to be regenerated by addition of wateror a suitable vehicle before use. Said liquid preparations can containconventional additives such as suspending agents, e.g. sorbitol, syrup,methylcellulose, gelatine, hydroxyethylcellulose,carboxymethylcellulose, aluminum stearate gel or hydrogenated ediblefats, emulsifying agents, e.g. lecithin, sorbitan monooleate, or acacia;non-aqueous vehicles (which may include edible oils), e.g. almond oil,fractionated coconut oil, oily esters such as glycerin esters, propyleneglycol, or ethyl alcohol; preservatives, e.g. methyl or propylp-hydroxybenzoate or sorbic acid and, if desired, conventional flavoursand dyes.

Oral formulations include conventional sustained release forms, such asenteric coated tablets or granules.

For parenteral administration, it is possible to prepare fluid dosageunits, containing the compound and a sterile vehicle. The compound,depending on the chosen vehicle and concentration, can be suspended ordissolved. Parenteral solutions are normally prepared by dissolving thecompound in a vehicle, sterilising by filtration, filling suitable vialsand sealing. Advantageously it is also possible to dissolve in thevehicle suitable adjuvants such as local anaesthetic, preservatives andbuffering agents. In order to increase stability, the composition can befrozen after filling the vial and removing water under vacuum.Parenteral suspensions are prepared substantially in the same way, withthe difference that the compound can be suspended rather than dissolvedin the vehicle, and they can be sterilised by treatment with ethyleneoxide before being suspended in the sterile vehicle. Advantageously, itis possible to include a surfactant or a wetting agent in thecomposition with the aim of easing the uniform distribution of thecompound of the invention.

The compounds of the invention can also be administered topically.Topical formulations may comprise, for example, an ointment, cream, gel,lotion, solution, paste or the like, and/or may be prepared so as tocontain liposomes, micelles, and/or microspheres. Ointments, as it iswell known in the art of pharmaceutical formulation, are semisolidpreparations that are typically based on petrolatum or other petroleumderivatives. Examples of ointments include leaginous ointment bases, forexample, vegetable oils, fats obtained from animals, and semisolidhydrocarbons obtained from petroleum, emulsifiable ointment bases, forexample, hydroxystearin sulfate, anhydrous lanolin and hydrophilicpetrolatum, emulsion ointment bases, for example, cetyl alcohol,glyceryl monostearate, lanolin and stearic acid and water-solubleointment bases prepared from polyethylene glycols of varying molecularweight. (See, e.g. Remington: The Science and Practice of Pharmacy,Twentieth Ed., Lippincolt Williams & Willcins: Philadelphia, 2000)Creams, as also well known to those skilled in the art, are viscousliquids or semisolid emulsions, and contain an oil phase, an emulsifierand an aqueous phase. The oil phase is generally comprised of petrolatumand a fatty alcohol such as cetyl or stearyl alcohol. The aqueous phaseusually contains a humectant. The emulsifier in a cream formulation ischosen among non-ionic, anionic, cationic or amphoteric surfactants.Single-phase gels contain organic macromolecules distributedsubstantially uniformly throughout the carrier liquid, which istypically aqueous, but also, preferably, contain an alcohol and,optionally, an oil. Preferred gelling agents are crosslinked acrylicacid polymers (such as “carbomer” polymers, e.g., carboxypolyalkylenesthat may be obtained commercially under the Carbopol trademark. Alsopreferred are hydrophilic polymers such as polyethylene oxides,polyoxyethylene-polyoxypropylene copolymers and polyvinylalcohol;cellulosic polymers such as hydroxypropyl cellulose, hydroxyethylcellulose, hydroxypropyl methylcellulose, hydroxypropyl methylcellulosephthalate, and methylcellulose; gums such as tragacanth and xanthan gum;sodium alginate; and gelatin. For the preparation of uniform gels,dispersing agents such as alcohol or glycerin can be added, or thegelling agent can be dispersed by trituration, mechanical mixing, and/orstirring.

The compounds of the invention may also be administered via transdermalrelease. Typical transdermal formulations include conventional aqueousand non-aqueous vectors, such as creams, oils, lotions or pastes or canbe provided as membranes or medicated plasters. In an embodiment, acompound of the invention is dispersed in a pressure-sensible plasteradhering to the skin. This formulation allows the compound to be spreadfrom the plaster to the patient through the skin. In order to obtain asustained drug release through the cutis, natural rubber and silicon canbe used as pressure-sensitive adhesives.

As it is common practice, the compositions are normally associated withwritten or printed instructions for use in the relevant treatments.

The invention also includes the use of said compounds of formula (I) inthe preparation of a medicament for prevention and/or treatment ofdiseases associated to deregulation of the activity of histonedeacetylases. Examples of such diseases are tumor diseases, Huntington'sdiseases caused by triplette amplification, degenerative diseases,ischemia, oxidation stress, inflammatory responses of the nervoussystem, epilepsy, diseases caused by protein aggregates, HIV infections,malaria, leishmanioses, infections caused by protozoa, fungi, phytotoxicagents, virus, parasites, autoimmune diseases, chronic host-directedimmune reaction, hypertrophy and cardiac disorders, fibrotic skindisease, muscular spinal or bulbar atrophy, bipolar disorders,psychiatric disorders, X-fragile syndrome, arthritis, renal diseases,psoriasis, intestinal-colitis diseases, beta thalassemia, respiratorydiseases, Rubinstein-Taybi syndrome.

Examples of tumors sensible to the present therapy are: leukemias andmyeloid and lymphoid lymphomas, acute and chronic myelodisplasticsyndromes, multiple myeloma, mammary tumors, lung tumors and pleuricmesoteliomas, cutaneous tumors, including basal carcinomas (basaliomas),melanomas, osteosarcomas, fibrosarcomas, rabdomyosarcomas,neuroblastomas, glioblastomas, cerebral tumors, testicular and ovariantumors, endometrial and prostatic tumors, thyroid carcinomas,colo-rectal tumors, gastric tumors and gastrointestinal adenocarcinomas,hepatic carcinomas, pancreatic carcinomas, renal tumors,teratocarcinomas and embryo carcinomas.

Further object of the invention is a method for prevention and/ortreatment of tumors characterised by administering pharmacologicallyuseful amounts of a compound of formula (I) to a patient in needthereof. Such use and method may include the co-administration,simultaneous or deferred with respect to the administration of thecompound of formula (I), of possible further agents with known activity,and any further drug useful for administration in joint therapy withsaid agents.

The dosage of the compounds of formula (I) is widely variable infunction of the patient and his status, the degree of progression of thedisease, the chosen way of administration, the chosen number of dailyadministrations, etc. As a reference they can be administered in adosage interval comprised between 0.001 and 1000 mg/Kg/day.

The invention is herein described by the following examples having nolimiting function.

EXPERIMENTAL PART

1. Chemistry

Methods

Unless otherwise noted, all starting materials were obtained fromcommercial suppliers and used without further purification.

Specifically, the following abbreviation may be used in the examples andthroughout the specification. g (grams) mg (milligrams) ml (millilitres)M (molar) μl (microliters) mmol (millimoles) THF (tetrahydrofuran) EtOAc(ethyl acetate) MeOH (methanol) EtOH (ethyl alcohol) DCM(dichloromethane) DMF (dimethylformamide) EDC(1-3(dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) PPh₃(triphenylphosphine) HOBT (1-hydroxybenzotriazole) DMA(dimethylacetamide) NMR (Nuclear Magnetic Reasonance) ¹H (proton) MHz(megahertz) Hz (Hertz) LC-MS (Liquid Chromatography Mass Spectrum) RT(Retention Time, minutes) TEA (triethylamine) NaH (sodium hydride)Na₂SO₄ (sodium sulphate) K₂CO₃ (potassium carbonate) Pd(OAc)₂ (palladiumacetate) KOH (potassium hydroxide) HCl (hydrochloric acid) n-BuLi(n-butyllithium) DMSO-d₆ (deutered dimethylsulfoxide)

All references to brine refer to a saturated aqueous solution of NaCl.Unless otherwise indicated, all temperatures are expressed in ° C.(degrees Centigrade) . . . .

¹H-NMR spectra were recorded on a Brucker 300 MHz. Chemical shifts areexpressed in parts of million (ppm, δ units). Coupling constants are inunits of hertz (Hz) Splitting patterns describe apparent multiplicitiesand are designated as s (singlet), d (doublet), t (triplet), q(quartet), quint (quintet), m (multiplet). b before the various symbolsmeans broad.

Melting points were determined on a Büchi 530 measurer. Infrared spectra(KBr) on a Perkin-Elmer Spectrum One instrument. Mass spectra (MS) wereobtained on a JEOL JMS-HX 100 spectrometer.

LCMS were recorded under the following conditions:

METHOD A: Pump 1525, 2777 Sample Manager, PDA 996, Micromass ZQ Singlequadrupole (Waters). Column Sunfire C18 (50×2.1 mm, 3.5 μm);

Flow rate: 0.25 ml/min splitting ratio MS:waste/1:4;

Mobile phase: A phase=water/CH₃CN 95/5+0.1% TFA; B phase=water/CH₃CN5/95+0.1% TFA. 0-1.0 min (A: 98%, B: 2%), 1.0-5.0 min (A: 0%, B: 100%),5.0-9.0 min (A: 0%, B: 100%), 9.1.0-12 min (A: 98%, B: 2%); UV detectionwavelength 254 nm or BPI; Injection volume: 5 μl

METHOD B: Pump 1525, 2777 Sample Manager, PDA 996, Micromass ZQ Singlequadrupole (Waters). Column Luna C18 (30×2.1 mm, 3.5 μm);

Flow rate: 0.25 ml/min splitting ratio MS:waste/1:4;

Mobile phase: A phase=water/CH₃CN 95/5+0.1% TFA; B phase=water/CH₃CN5/95+0.1% TFA. 0-1.0 min (A: 98%, B: 2%), 1.0-5.0 min (A: 0%, B: 100%),5.0-9.0 min (A: 0%, B: 100%), 9.1.0-12 min (A: 98%, B: 2%); UV detectionwavelength 254 nm or BPI; Injection volume: 5 μl

METHOD C: Pump 1525, 2777 Sample Manager, PDA 996, Micromass ZQ Singlequadrupole (Waters). Column XTerra C18 (50×2.1 mm, 2.5 μm); Flow rate:0.25 ml/min splitting ratio MS:waste/1:4;

Mobile phase: A phase=water/CH₃CN 95/5+0.1% TFA; B phase=water/CH₃CN5/95+0.1% TFA. 0-1.0 min (A: 98%, B: 2%), 1.0-5.0 min (A: 0%, B: 100%),5.0-9.0 min (A: 0%, B: 100%), 9.1.0-12 min (A: 98%, B: 2%); UV detectionwavelength 254 nm or BPI; Injection volume: 51

METHOD D: Pump 1525, 2777 Sample Manager, PDA 996, Micromass ZQ Singlequadrupole (Waters). Column Atlantis dC18 (100×2.1 mm, 3 μm); Flow rate:0.25 ml/min splitting ratio MS:waste/1:4;

Mobile phase: A phase=water/CH₃CN 95/5+0.1% TFA; B phase=water/CH₃CN5/95+0.10% TFA. 0-10 min (A: 98%, B: 2%), 1.0-5.0 min (A: 0%, B: 100%),5.0-9.0 min (A: 0%, B: 100%), 9.1.0-12 min (A: 98%, B: 2%); UV detectionwavelength 254 nm or BPI; Injection volume: 511

METHOD E: Pump 1525, 2777 Sample Manager, PDA 996, Micromass ZQ Singlequadrupole (Waters). Column Disc. HS F5 C18 (50×2.1 mm, 3 μm); Flowrate: 0.25 ml/min splitting ratio MS:waste/1:4;

Mobile phase: A phase=water/CH₃CN 95/5+0.1% TFA; B phase=water/CH₃CN5/95+0.1% TFA. 0-1.0 min (A: 98%, B: 2%), 1.0-5.0 min (A: 0%, B: 100%),5.0-9.0 min (A: 0%, B: 100%), 9.1.0-12 min (A: 98%, B: 2%); UV detectionwavelength 254 nm or BPI; Injection volume: 5 μl

METHOD F: Pump 1525, 2777 Sample Manager, PDA 996, Micromass ZQ Singlequadrupole (Waters). SunFire C18 (50×2.1 mm, 3.5 μm); Flow rate: 0.25ml/min splitting ratio MS:waste/1:4;

Mobile phase: A phase=HCOO⁻NH₄ ⁺ pH=8/MeOH/CH₃CN 85/10/5; Bphase=HCOO⁻NH₄ ⁺ pH=8/MeOH/CH₃CN May 10, 1985.0-1.0 min (A: 98%, B: 2%),1.0-5.0 min (A: 0%, B: 100%), 5.0-9.0 min (A: 0%, B: 100%), 9.1.0-12 min(A: 98%, B: 2%); UV detection wavelength 254 nm or BPI; Injectionvolume: 5 μl

All mass spectra were taken under electrospray ionisation (ESI) methods.

Most of the reactions were monitored by thin-layer chromatography on 0.2mm Merck silica gel plates (60F-254), visualized with UV light. Flashcolumn chromatography was performed on silica gel 60 (0.04-0.063 mm)Merck.

Synthesis of ethyl 4-formylcinnamate

The synthesis was performed according to Saigo et al., Bull. Chem. Soc.Jpn., 1995, 68, 2355-2362.

Synthesis of n-butyl 3-formylcinnamate

A 10 mL Schenk tube was dried in oven and loaded under N₂ with K₃PO₄(2.37 g, 11.16 mmol) and DMA (2.0 mL). 3-iodobenzaldeide (1.85 g, 7.97mmol) and n-butylacrylate. (2.28 mL, 15.94 mmol) were then added bysyringe. A solution of Pd(OAc)₂ (0.18 g, 0.797 mmol) in DMA (0.5 mL) wasfurther added by syringe. The Schlenk tube was then sealed undernitrogen and placed in a pre-heated oil bath at 140° C., and thereaction mixture was stirred for 24 h. After cooling to roomtemperature, the reaction mixture was poured in water (50 mL) andextracted with ethyl acetate (3×50 mL). The combined organic extractswere washed with brine, dried (Na₂SO₄), and concentrated under vacuum todryness. The crude product was purified by chromatographic column onsilica gel, eluting with n-hexane/ethylacetate/methanol 12/3/1 (yield:47%). ¹H NMR (CDCl₃) δ: 0.91-0.96 (t, 3H, OCH₂CH₂CH₂CH₃), 1.39-1.42 (m,2H, OCH₂CH₂CH₂CH₃), 1.65-1.68 (m, 2H, OCH₂CH₂CH₂CH₃), 4.17-4.21 (m, 2H,OCH₂CH₂CH₂CH₃), 6.48-6.53 (d, 1H, ArCH═CHCO), 7.52-7.54 (m, 1H, benzeneH-5), 7.53-7.75 (m, 2H, ArCH═CHCO and benzene H-6), 7.84-7.86 (m, 1H,benzene H-4), 7.99 (m, 1H, benzene H-2), 10.01 (s, 1H, CHO).

n-butyl 4-cinnamoylcinnamate shown in Scheme 3 was prepared using asimilar procedure.

General Procedure for the Synthesis of 3- and 4-Substituted CinnamicAcids

Example: synthesis of3-[3-[3-(3-fluorophenyl)-3-oxopropen-1-il]benzenepropenoic acid.

A mixture of n-butyl-4-formylcinnamate (6.0 mmol, 1.40 g),3-fluoroacetophenone (6.0 mmol, 0.93 g), and KOH 2 N (24.0 mmol, 12.4mL) in ethanol (15 mL)/water (15 mL) was stirred at room temperature for24 h. Thereafter, the solution was poured in water (100 mL) andacidified with HCl 2N. The precipitate thus obtained was filtered andrecrystallised obtaining the pure acid. Yield: 72%; mp: 157-159° C.,recrystallisation solvent: acetonitrile. ¹H NMR (DMSO-d₆) δ 6.69-6.73(d, 1H, CH═CHCOOH), 7.48-7.54 (m, 2H, benzene H), 7.61-7.65 (m, 2H,benzene H and COCH═CH), 7.74-7.80 (m, 2H, benzene H and COCH═CH),7.88-7.90 (m, 1H, benzene H), 8.02-8.06 (m, 3H, benzene H andCH═CHCOOH), 8.31 (s, 1H, benzene H), 12.50 (bs, 1H, OH).

4-bromophenyl-2-phenylvinylketone shown in Scheme 3 was prepared using asimilar procedure.

General Procedure for the Synthesis of 3- and 4-SubstitutedN-Hydroxycinnamic amides

Example: synthesis ofN-hydroxy-3-[3-[3-(3-fluorophenyl)-3-oxopropen-1-yl]benzenepropenamide.

A cooled solution (0° C.) of3-[3-[3-(3-fluorophenyl)-3-oxopropen-1-il]benzenepropenoic acid (4.2mmol, 1.2 g) in dried THF (10 mL), was added to ethyl chloroformiate(5.0 mmol, 0.5 mL) and triethylamine (5.4 mmol, 0.8 mL), and the mixturewas stirred for 10 min. The reaction mixture was filtered, and thefiltrate was added to O-(2-methoxy-2-propyl)hydroxylamine (4.71 mmol,0.35 mL) (Tetrahedron 1988, 44, 6013-20). The solution was stirred for15 min at 0° C., then evaporated under reduced pressure, and the residuewas diluted in methanol (10 mL). The solution of the O-protectedhydroxamate was added to an Amberlyst® 15 ion exchange resin (0.3 g),and the resulting mixture was stirred at 45° C. for 1 h.

Thereafter, the reaction mixture was filtered and the filtrate wasconcentrated under vacuum obtaining the crude N-hydroxyamide, which wasthen purified by crystallisation. Yield: 74%; mp: 166-168° C.,recrystallisation solvent: acetonitrile. ¹H NMR (DMSO-d₆) δ 6.54-6.58(d, 1H, CH═CHCOOH), 7.48-7.56 (m, 3H, benzene H), 7.62-7.66 (m, 2H,benzene H), 7.76-7.80 (m, 1H, COCH═CH), 7.87-7.89 (m, 1H, benzene H),7.96-8.03 (m, 3H, benzene H, COCH═CH and CH═CHCOOH), 8.15 (s, 1H,benzene H), 9.07 (s, 1H, NH), 10.80 (s, 1H, OH).

By following the aforementioned general procedures, a number ofcompounds were synthesised, whose structures and synthesis data arereported in table 1. TABLE 1

Yield Compound Ar (%) χ Mp ° C. MC1632 Ph 62 C6H6/CH3CN 180-181 MC16452-Cl-Ph 53 CH3CN 158-160 MC1622 3-Cl-Ph 60 MeOH 205-206 MC1624 2-F-Ph 51C6H6/CH3CN 155-156 MC1610 3-F-Ph 67 C6H12/C6H6 175-176 MC1625 4-F-Ph 74MeOH 208-209 MC1644 2-Me-Ph 48 CH3CN 140-142 MC1623 3-Me-Ph 56 MeOH210-212 MC1639 4-Me-Ph 65 MeOH 226-228 MC1652 1-naphthyl 65 CH3CN134-136 MC1671 5-dihydrobenzo- 76 CH3CN 179-181 dec. furan

Yield Compound Ar (%) χ Mp ° C. MC1646 Ph 64 C₆H₆/CH₃CN 108-110 MC16702-Cl-Ph 61 CH₂Cl₂/petr. ether 104-106 MC1672 3-Cl-Ph 68 THF/petr. ether177-179 MC1661 2-F-Ph 58 C₆H₁₂/C₆H₆  98-100 MC1653 3-F-Ph 74 CH₃CN166-168

Yield Compound (%) χ Mp ° C. MC1631 57 C₆H₆/CH₃CN 147-149

Example 13-[3-Fluoro-4-(3-oxo-3-phenyl-propenyl)-phenyl]-N-hydroxy-acrylamide

Step A

A solution of 4-bromo-2-fluoro benzaldehyde (2 g, 9.9 mmol) in DMF (50ml) and triethylamine (6 ml) was degassed flushing N₂ for 30 min. PPh₃(130 mg, 0.459 mmol), Pd(OAc)₂ (44.3 mg, 0.20 mmol), NaHCO₃ (1.6 g, 18.6mmol) and tert-butyl acrylate (1.27 g, 9.9 mmol) were added and theresulting mixture was heated to reflux for 4 h. Additional tert-butylacrylate (633 mg) and Pd(OAc)₂ (20 mg) were added and the mixture wasstirred at 100° C. for 3 h then the solution was diluted with H₂O andextracted with Et₂O. The organic layer was dried over Na₂SO₄ and thesolvent was evaporated under vacuo to give the crude product that waspurified by silica gel chromatography (petroleum ether/EtOAc 95:5). Thecollected fractions gave 2 g of 3-(3-fluoro-4-formyl-phenyl)-acrylicacid tert-butyl ester.

Yield: 80%

Step B

3-(3-fluoro-4-formyl-phenyl)-acrylic acid tert-butyl ester (2 g, 8 mmol)was dissolved in DCM (23 ml) and trifluoroacetic acid (6 ml). Themixture was stirred at room temperature for 6 h then the solvent wasevaporated under vacuo giving 1.62 g of3-(3-fluoro-4-formyl-phenyl)-acrylic acid

Yield: quantitative

Step C

3-(3-fluoro-4-formyl-phenyl)-acrylic acid (500 mg, 2.57 mmol) wasdissolved in ethanol/water (1:1, 10 ml) and 1.7M KOH (3 ml). To theresulting solution was added acetophenone (0.3 ml, 2.57 mmol). Themixture was stirred at room temperature overnight then acidified with10% HCl and extracted with EtOAc. The organic layer was dried overNa₂SO₄ and the solvent was evaporated under vacuo. The crude product wastriturated in EtOAc and filtered to give 560 mg of3-[3-fluoro-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylic acid.

Yield: 73%

Step D

3-[3-fluoro-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylic acid (450 mg,1.52 mmol) was dissolved in THF (10 ml) and DMF (1 ml). To the resultingsolution, HOBT (413 mg, 3.04 mmol), EDC (580 mg, 3.04 mmol), TEA (0.423ml, 3.04 mmol) and NH₂OTHP (213 mg, 1.82 mmol) were added. The mixturewas stirred overnight at RT then partitioned between water and EtOAc.The organic extract was washed with water then dried over Na₂SO₄ andevaporated under vacuo.

The crude product was purified by silica gel chromatography (petroleumether/EtOAc 1:1) and the resulting oil was dissolved in DCM and treatedwith HCl/Et₂O for 1 h. The precipitate was filtered on Buckner funneland washed with DCM/MeOH to give 200 mg of3-[3-fluoro-4-(3-oxo-3-phenyl-propenyl)-phenyl]-N-hydroxy-acrylamide.

LC-MS Method=B RT=6.01; (ES+) gave MH⁺: 312.2

¹H-NMR (DMSO-d₆,): 10.84 (s br, 1H); 9.07 (s br, 1H); 8.15 (m, 3H); 8.00(d, 1H); 7.81 (d, 1H); 7.69 (ddd, 1H); 7.63-7.52 (m, 4H); 7.48 (d, 1H);6.60 (d, 1H).

The compounds in Table 2 were prepared according to the proceduredescribed above (steps A-D or C-D when the intermediate was commerciallyavailable). TABLE 2 LC-MS Ex method; No structure Compound name RT minMH+ ¹H-NMR (DMSO-d₆) δ:  2

3-[3-chloro-4-(3-oxo-3- phenyl-propenyl)- phenyl]-N-hydroxy- acrylamideB, 6.33 328.1 8.26 (d, 1 H); 8.17 (d, 2 H); 8.02 (s, 2 H); 7.78 (s, 1H); 7.73-7.55 (m, 4 H); 7.47 (d, 1 H); 6.63 (d, 1 H)  3

3-[3-chloro-4-(3-oxo-3- o-tolyl-propenyl)- phenyl]-N-hydroxy- acrylamideA, 6.92 342.0 8.13 (d, 1 H); 7.77 (d, 1 H); 7.77-7.67 m, 2 H); 7.61 (d,1 H); 7.51 (d, 1 H); 7.50-7.41 (m, 2 H); 7.36 (m, 2 H); 6.62 (d, 1 H);2.41 (s, 3 H)  4

3-{3-chloro-4-[3-(2- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 6.72 358.0 8.01 (d, 1 H); 7.78 (d, 1 H); 7.76(s, 1 H); 7.63-7.49 (m, 4 H); 7.45 (d, 1 H); 7.21 (d, 1 H); 7.08 (dd, 1H); 6.61 (d, 1 H); 3.88 (s, 3 H)  5

3-{3-chloro-4-[3-(2- fluoro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide B, 6.30 346.2 10.75 (s br, 1 H); 9.13 (s br, 1 H);8.04 (d, 1 H); 7.90 (d, 1 H); 7.83 (ddd, 1 H); 7.78 (s, 1 H); 7.74-7.65(m, 1 H); 7.63 (d, 1 H); 7.58 (dd, 1 H); 7.46 (d, 1 H); 7.41 (dd, 1 H);7.38 (d, 1 H); 6.60 (d, 1 H).  6

3-{3-chloro-4-[3-(2- chloro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 6.89 362.0 8.09 (d, 1 H); 7.76 (s br, 1 H); 7.70(d, 1 H); 7.67-7.47 (m, 5 H); 7.45 (d, 1 H); 7.39 (d, 1 H); 6.62 (d, 1H)  7

3-[3-chloro-4-(3-oxo-3- m-tolyl-propenyl)- phenyl]-N-hydroxy- acrylamideB, 6.54 342.2 10.74 (s br, 1 H); 9.08 (s br, 1 H); 8.26 (d, 1 H); 8.02(s, 2 H); 7.97 (m, 2 H); 7.79 (s, 1 H); 7.75 (d, 1 H); 7.54-7.41 (m, 3H); 6.62 (d, 1 H); 2.43 (s, 3 H)  8

3-{3-chloro-4-[3-(3- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 7.01 358.0 8.28 (d, 1 H); 8.03 and 7.98 (ABq, 2H); 7.78 (m, 2 H); 7.64 (m, 2 H); 7.51 (dd, 1 H); 7.47 (d, 1 H); 7.26(ddd, 1 H); 6.62 (d, 1 H); 3.86 (s, 3 H)  9

3-{3-chloro-4-[3-(3- fluoro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide B, 6.49 346.1 10.80 (s br, 1 H); 9.08 (s br, 1 H);8.30 (d, 1 H); 8.05 (s, 2 H); 8.02 (dd, 1 H); 7.99 (ddd, 1 H); 7.79 (s,1 H); 7.70-7.61 (m, 2 H); 7.55 (ddd, 1 H); 7.48 (d, 1 H); 6.63 (d, 1 H)10

3-{3-chloro-4-[3-(3- chloro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 7.33 362.0 10.78 (s br, 1 H); 9.23 (s br, 1 H);8.31 (d, 1 H); 8.22 (dd, 1 H); 8.13 (ddd, 1 H); 8.05 (s, 2 H); 7.79 (d,1 H); 7.76 (ddd, 1 H); 7.66 (m, 1 H); 7.63 (dd, 1 H); 7.47 (d, 1 H);6.63 (d, 1 H) 11

3-[3-Chloro-4-(3-oxo-3- p-tolyl-propenyl)- phenyl]-N-hydroxy- acrylamideA, 7.12 342.0 8.26 (d, 1 H); 8.09 (d, 2 H); 8.01 (s, 1 H); 7.78 (s, 1H); 7.64 (d, 1 H); 7.47 (d, 1 H); 7.40 (d, 2 H); 6.63 (d, 1 H); 2.42 (s,3 H) 12

3-{3-chloro-4-[3-(4- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide B, 6.28 358.1 10.78 (s br, 1 H); 9.08 (s br, 1 H);8.25 (d, 1 H); 8.19 (d, 2 H); 8.03 and 7.99 (ABq, 2 H); 7.77 (s, 1 H);7.64 (d, 1 H); 7.47 (d, 1 H); 7.10 (d, 2 H); 6.61 (d, 1 H); 3.88 (s, 3H) 13

3-{3-chloro-4-[3-(4- fluoro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 7.01 346.1 8.28 (dd, 2 H); 8.26 (d, 1 H); 8.03 (s,2 H); 7.78 (s, 1 H); 7.64 (d, 1 H); 7.46 (d, 1 H); 7.41 (dd, 2 H); 6.65(d, 1 H) 14

3-{3-chloro-4-[3-(4- chloro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 7.33 362.0 8.27 (d, 1 H); 8.20 (d, 2 H); 8.03 (s,2 H); 7.77 (s, 1 H); 7.65 (d, 2 H); 7.65 (d, 1 H); 7.46 (d, 1 H); 6.65(d, 1 H) 15

3-[3-chloro-4-(3-oxo-3- thiophen-2-yl-propenyl)- phenyl]-N-hydroxy-acrylamide B, 6.28 334.1 10.73 (s br, 1 H); 8.36 (dd, 1 H); 8.25 (d, 1H); 8.10 (dd, 1 H); 8.01 (d, 1 H); 7.96 (d, 1 H); 7.79 (d, 1 H); 7.66(dd, 1 H); 7.47 (d, 1 H); 7.34 (dd, 1 H); 6.23 (d, 1 H) 16

3-[3-fluoro-4-(3-oxo-3- o-tolyl-propenyl)- phenyl]-N-hydroxy- acrylamideA, 6.81 326.1 8.02 (dd, 1 H); 7.66 (dd, 1 H); 7.59-7.42 (m, 6 H); 7.36(m, 2 H); 6.60 (d, 1 H); 2.40 (s, 3 H) 17

3-{3-fluoro-4-[3-(2- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide F, 6.55 342.1 8.91 (dd, 1 H); 7.61-7.42 (m, 7 H);7.21 (d, 1 H); 7.07 (ddd, 1 H); 6.58 (d, 1 H); 3.88 (s, 3 H) 18

3-{3-fluoro-4-[3-(2- fluoro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 6.82 330.0 7.98 (dd, 1 H); 7.82 (ddd, 1 H);7.74-7.64 (m, 2 H); 7.62-7.47 (m, 4 H); 7.46-7.35 (m, 2 H); 6.61 (d, 1H) 19

3-{4-[3-(2-chloro- phenyl)-3-oxo-propenyl]- 3-fluoro-phenyl}-N-hydroxy-acrylamide C, 5.99 345.9 7.98 (dd, 1 H); 7.64-7.34 (m, 9 H);6.61 (d, 1 H) 20

3-[3-fluoro-4-(3-oxo-3- m-tolyl-propenyl)- phenyl]-N-hydroxy- acrylamideA, 6.97 326.1 8.16 (dd, 1 H); 7.99 (d, 1 H); 7.94 (m, 2 H); 7.80 (d, 1H); 7.59-7.43 (m, 5 H); 6.61 (d, 1 H); 2.43 (s, 3 H) 21

3-{3-fluoro-4-[3-(3- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 6.70 342.1 8.17 (dd, 1 H); 7.98 (d, 1 H); 7.81 (d,1 H); 7.76 (ddd, 1 H); 7.61 (dd, 1 H); 7.58-7.43 (m, 4 H); 7.26 (ddd, 1H); 6.62 (d, 1 H); 3.86 (s, 3 H) 22

3-{3-fluoro-4-[3-(3- fluoro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide B, 7.38 330.2 8.19 (dd, 1 H); 8.01 (d, 1 H); 8.00 (d,1 H); 7.95 (ddd, 1 H); 7.84 (d, 1 H); 7.70-7.51 (m, 4 H); 7.49 (d, 1 H);6.62 (d, 1 H) 23

3-{4-[3-(3-chloro- phenyl)-3-oxo-propenyl]- 3-fluoro-phenyl}-N-hydroxy-acrylamide A, 7.17 346.0 8.20 (dd, 1 H); 8.18 (m, 1 H); 8.10(ddd, 1 H); 8.01 (d, 1 H); 7.84 (d, 1 H); 7.76 (ddd, 1 H); 7.62 (dd, 1H); 7.54 (m, 2 H); 7.48 (d, 1 H), 6.63 (d, 1 H) 24

3-[3-fluoro-4-(3-oxo-3- p-tolyl-propenyl)- phenyl]-N-hydroxy- acrylamideB, 6.43 326.1 10.82 (s br, 1 H); 9.18 (s br, 1 H); 8.15 (dd, 1 H); 8.06(d, 2 H); 8.00 (d, 1 H); 7.79 (d, 1 H); 7.54 (m, 2 H); 7.48 (d, 1 H);7.40 (d, 2 H); 6.59 (d, 1 H); 2.42 (s, 3 H) 25

3-{3-fluoro-4-[3-(4- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 6.60 342.1 8.16 (d, 2 H); 8.15 (dd, 1 H); 8.01 (d,1 H); 7.78 (d, 1 H); 7.53 (m, 2 H); 7.47 (d, 1 H); 7.10 (d, 2 H); 6.61(d, 1 H); 3.88 (s, 3 H) 26

3-{3-fluoro-4-[3-(4- fluoro-phenyl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 6.78 330.1 8.25 (dd, 2 H); 8.16 (dd, 1 H); 8.01(d, 1 H); 7.81 (d, 1 H); 7.53 (m, 2 H); 7.43 (m, 1 H); 7.41 (dd, 2 H);6.62 (d, 1 H) 27

3-{4-[3-(4-chloro- phenyl)-3-oxo-propenyl]- 3-fluoro-phenyl}-N-hydroxy-acrylamide A, 7.15 346.0 8.18 (d, 2 H); 8.16 (dd, 1 H); 8.01 (d,1 H); 7.82 (d, 1 H); 7.66 (d, 2 H); 7.54 (m, 2 H); 7.48 (d, 1 H); 6.62(d, 1 H) 28

3-[3-fluoro-4-(3-oxo-3- thiophen-2-yl-propenyl)- phenyl]-N-hydroxy-acrylamide B, 6.14 318.1 10.85 (s br, 1 H); 8.32 (dd, 1 H); 8.15 (dd, 1H); 8.09 (dd, 1 H); 7.94 (d, 1 H); 7.79 (d, 1 H); 7.53 (m, 2 H); 7.48(d, 1 H); 7.33 (dd, 1 H); 6.65 (d, 1 H) 29

3-{3-fluoro-4-[3-(4- morpholin-4-yl-phenyl)- 3-oxo-propenyl]-phenyl}-N-hydroxy- acrylamide B, 6.09 397.1 10.79 (s br, 1 H); 8.14 (dd,1 H); 8.06 (d, 2 H); 7.98 (d, 1 H); 7.75 (d, 1 H); 7.59-7.39 (m, 3 H);7.04 (d, 2 H); 6.59 (d, 1 H); 3.75 (m, 4 H); 3.40 (m, 4 H) 30

N-hydroxy-3-{4-[3-(2- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-acrylamide B, 6.08 324.1 7.76 (d, 2 H); 7.61 (d, 2 H); 7.59-7.40 (m, 5H); 7.20 (d, 1 H); 7.06 (ddd, 1 H); 6.55 (d, 1 H); 3.87 (s, 3 H) 31

N-hydroxy-3-{4-[3- oxo-3-(2-trifluoromethyl- phenyl)-propenyl]-phenyl}-acrylamide E, 6.53 361.8 7.89 (d, 1 H); 7.82 (dd, 1 H); 7.79 (d,2 H); 7.76 (dd, 1 H); 7.68 (d, 1 H); 7.61 (dd, 2 H); 7.46 (d, 1 H); 7.35(d, 1 H); 7.30 (d, 1 H); 6.56 (d, 1 H) 32

N-hydroxy-3-{4-[3- oxo-3-(2-trifluoro- methoxy-phenyl)-propenyl]-phenyl}- acrylamide A, 6.65 377.8 7.81 (d, 2 H); 7.78 (dd, 1H); 7.73 (ddd, 1 H); 7.62 (d, 2 H); 7.60-7.50 (m, 3 H); 7.47 (d, 1 H);7.39 (d, 1 H); 6.57 (d, 1 H) 33

3-{4-[3-(2-bromo- phenyl)-3-oxo-propenyl]- phenyl}-N-hydroxy- acrylamideD, 7.42 371.7 7.80 (d, 2 H); 7.76 (d, 1 H); 7.62 (d, 2 H); 7.57-7.42 (m,4 H); 7.38 (d, 1 H); 7.28 (d, 1 H); 6.56 (d, 1 H) 34

N-hydroxy-3-{4-[3-(3- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-acrylamide A, 6.41 324.0 11.59 (s br, 1 H); 10.76 (s br, 1 H); 7.95 (d,1 H); 7.94 (d, 1 H); 7.92 (s, 1 H); 7.77 (ddd, 1 H); 7.74 (d, 1 H);7.68-7.58 (m, 3 H); 7.50 (dd, 1 H); 7.49 (d, 1 H); 7.25 (ddd, 1 H); 6.56(d, 1 H); 3.86 (s, 3 H) 35

3-{4-[3-(3-bromo- phenyl)-3-oxo-propenyl]- phenyl}-N-hydroxy- acrylamideA, 6.85 371.7 10.77 (s br, 1 H); 9.05 (s br, 1 H); 8.33 (dd, 1 H); 8.16(ddd, 1 H); 7.98 (d, 1 H); 7.96 (d, 2 H); 7.88 (ddd, 1 H); 7.77 (d, 1H); 7.66 (d, 2 H); 7.55 (dd, 1 H); 7.50 (d, 1 H); 6.57 (d, 1 H) 36

N-hydroxy-3-{4-[3-(4- methoxy-phenyl)-3-oxo- propenyl]-phenyl}-acrylamide A, 6.33 324.0 8.17 (d, 2 H); 7.96 (d, 1 H); 7.91 (d, 2 H);7.70 (d, 1 H); 7.64 (d, 2 H); 7.49 (d, 1 H); 7.03 (d, 2 H); 6.56 (d, 1H); 3.88 (s, 3 H) 37

N-Hydroxy-3-{4-[3-oxo- 3-(4-trifluoromethyl- phenyl)-propenyl]-phenyl}-acrylamide A, 6.95 361.6 10.73 (s br, 1 H); 10.23 (s br, 1 H);8.33 (d, 2 H); 7.97 (d, 1 H); 7.94 (d, 2 H); 7.79 (d, 1 H); 7.66 (d, 2H); 7.49 (d, 1 H); 6.59 (d, 1 H) 38

N-hydroxy-3-{4-[3-oxo- 3-(4-trifluoromethoxy- phenyl)-propenyl]-phenyl}-acrylamide A, 7.01 378.0 8.29 (d, 2 H); 7.97 (d, 1 H); 7.93 (d,2 H); 7.76 (d, 1 H); 7.65 (d, 2 H); 7.54 (d, 2 H); 7.49 (d, 1 H); 6.59(d, 1 H) 39

3-{4-[3-(4-bromo- phenyl)-3-oxo-propenyl]- phenyl}-N-hydroxy- acrylamideA, 6.88 371.7 8.10 (d, 2 H); 7.94 (d, 1 H); 7.92 (d, 2 H); 7.79 (d, 2H); 7.75 (d, 1 H); 7.65 (d, 2 H); 7.48 (d, 1 H); 6.57 (d, 1 H) 40

3-{4-[3-(4-diethylamino- phenyl)-3-oxo-propenyl]- phenyl}-N-hydroxy-acrylamide A, 6.36 365.1 10.76 (s br, 1 H); 9.04 (s br, 1 H); 8.02 (d, 2H); 7.91 (d, 1 H); 7.88 (d, 2 H); 7.63 (d, 2 H); 7.62 (d, 1 H); 7.49 (d,1 H); 6.73 (d, 2 H); 6.53 (d, 1 H); 3.46 (q, 4 H); 1.14 (t, 6H) 41

N-hydroxy-3-{4-[3-(4- morpholin-4-yl-phenyl)- 3-oxo-propenyl]-phenyl}-acrylamide B, 5.78 379.2 8.08 (d, 2 H); 7.95 (d, 1 H); 7.90 (d,2 H); 7.66 (d, 1 H); 7.63 (d, 2 H); 7.48 (d, 1 H); 7.03 (d, 2 H); 6.56(d, 1 H); 3.75 (m, 4 H); 3.34 (m, 4 H). 42

3-[4-(3-furan-2-yl-3-oxo- propenyl)-phenyl]- acrylamide A. 6.25 284.18.07 (dd, 1 H); 7.89 (d, 2 H); 7.83 (dd, 1 H); 7.73 (s, 2 H); 7.65 (d, 2H); 7.48 (d, 1 H); 6.80 (dd, 1 H); 6.58 (d, 1 H) 43

N-hydroxy-3-[4-(3-oxo- 3-thiophen-2-yl- propenyl)-phenyl]- acrylamide B,6.11 300.1 8.33 (dd, 1 H); 8.06 (dd, 1 H); 7.92 (d, 2 H); 7.90 (d, 1 H);7.73 (d, 1 H); 7.65 (d, 2 H); 7.48 (d, 1 H); 7.32 (dd, 1 H); 6.58 (d, 1H) 44

N-hydroxy-3-{4-[3-oxo- 3-(1H-pyrrol-2-yl)- propenyl]-phenyl}- acrylamideA, 6.05 283.1 11.96 (s, 1 H); 10.76 (s br, 1 H); 9.05 (s br, 1 H); 7.87(d, 2 H); 7.72 (d, 1 H); 7.64 (d, 1 H); 7.63 (d, 2 H); 7.48 (d, 1 H);7.37 (m, 1 H); 7.17 (m, 1 H); 6.54 (d, 1 H); 6.28 (m, 1 H) 45

3-[4-(3-benzofuran-2-yl- 3-oxo-propenyl)-phenyl]- N-hydroxy-acrylamideB, 6.21 334.2 8.31 (s, 1 H); 7.94 (d, 2 H); 7.92 (d, 1 H); 7.89 (d, 1H); 7.82 (d, 1 H); 7.75 (d, 1 H); 7.67 (d, 2 H); 7.57 (ddd, 1 H); 7.49(d, 1 H); 7.40 (ddd, 1 H); 6.59 (d, 1 H) 46

3-[4-(3-benzo[b]thiophen-2-yl-3-oxo- propenyl)-phenyl]-N-hydroxy-acrylamide B, 6.49 350.1 10.76 (s br, 1 H); 9.05 (s br, 1 H);8.77 (s, 1 H); 8.07 (d, 1 H); 8.05 (d, 2 H); 7.97 (d, 2 H); 7.79 (d, 1H); 7.68 (d, 2 H); 7.60-7.46 (m, 2 H); 7.52 (d, 1 H); 6.58 (d, 1 H) 47

N-hydroxy-3-[4-(3-oxo- 3-thiophen-3-yl- propenyl)-phenyl]- acrylamide B,6.0  300.1 (1H DMSO): 8.82 (dd, 1 H); 7.90 (m, 2 H); 7.87 (d, 1 H); 7.70(d, 1 H); 7.70-7.61 (m, 4 H); 7.47 (d, 1 H); 7.57 (d, 1 H). 48

N-hydroxy-3-{4-[3-(3- methoxy-4-morpholin-4- ylmethyl-phenyl)-3-oxo-propenyl]-phenyl}- acrylamide B, 5.11 423.2 10.88 (s br, 1 H); 9.11 (sbr, 1 H); 8.54 (s, 1 H); 8.28 (dd, 1 H); 8.04 (d, 1 H); 7.96 (d, 2 H);7.74 (d, 1 H); 7.64 (d, 2 H); 7.48 (d, 1 H); 7.29 (d, # 1 H); 6.57 (d, 1H); 4.40 (s, 2 H); 3.98 (s, 3 H); 3.94 (m, 2 H); 3.82 (m, 2 H); 3.32 (m,2 H); 3.17 (m, 2 H)

Example 493-{4-[3-(3,4-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide

Step A

A solution of 4-bromo benzaldehyde (2 g, 10.8 mmol) in DMF (50 ml) andtriethylamine (3.4 ml, 27 mmol) was degassed flushing N₂ for 30 min.PPh₃ (141 mg, 0.54 mmol), Pd(OAc)₂ (48.4 mg, 0.21 mmol), NaHCO₃ (1.84 g,21.6 mmol) and tert-butyl acrylate (1.58 ml, 10.8 mmol) were added andthe resulting mixture was heated to reflux for 3 h. Additional Pd(OAc)₂(24 mg) was added and the mixture was heated to 100° C. for 1 h. Thesolution was diluted with H₂O and extracted with Et₂O. The organic layerwas dried over Na₂SO₄ and the solvent was evaporated under vacuo to givethe crude product that was triturated in isopropyl ether to give 1.6 gof 3-(4-formyl-phenyl)-acrylic acid tert-butyl ester.

Yield: 70%

Step B

3-(4-formyl-phenyl)-acrylic acid tert-butyl ester (150 mg, 0.64 mmol)and KOH (72 mg, 1.28 mmol)) were dissolved in ethanol/water (1:1, 5 ml)and 3,4-difluoroacetophenone (83.2 μl, 0.64 mmol) was added to theresulting solution. The resulting mixture was stirred at roomtemperature overnight and then diluted with H₂O. The precipitate wasfiltered and dried under vacuo to give 210 mg of3-{4-[3-(3,4-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-acrylic acidtert-butyl ester.

Yield: 88%.

Step C

3-{4-[3-(3,4-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-acrylic acidtert-butyl ester (210 mg, 0.56 mmol) was dissolved in DCM (5 ml) andtrifluoroacetic acid was added (2 ml). The reaction was stirred at roomtemperature for 12 h. The solvent was evaporated under vacuo giving 200mg of 3-{4-[3-(3,4-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-acrylicacid.

Yield: quantitative

Step D

3-{4-[3-(3,4-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-acrylic acid (100mg, 0.32 mmol) was dissolved in DCM (10 ml). HOBT (72 mg, 0.44 mmol),EDC (91 mg, 0.44 mmol), TEA (129 μl, 0.96 mmol) and NH₂OTHP (55 mg, 0.32mmol) were added to the resulting solution. The mixture was stirredovernight at room temperature then partitioned between water and EtOAc.The organic extract was washed with water then dried over Na₂SO₄ andevaporated under vacuo.

The crude product was purified on silica gel chromatography (petroleumether/EtOAc 8:2) and the resulting oil was dissolved in DCM and treatedwith HCl/Et₂O for 1 h. The precipitate was filtered on Buckner funneland dried under vacuo to give 40 mg of3-{4-[3-(3,4-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide.

Yield: 40%

LC-MS Method=B RT=6.29; (ES+) gave MH⁺: 330.1

¹H-NMR (DMSO-d₆,) δ: 10.72 (s br, 1H); 9.16 (s br, 1H); 8.25 (ddd, 1H);8.08 (m, 1H); 7.98 (d, 1H); 7.95 (d, 2H); 7.77 (d, 1H); 7.70-7.60 (m,3H); 7.49 (d, 1H); 6.57 (d, 1H)

The compounds reported in Table 3 were prepared according to theprocedure described above TABLE 3 LC-MS Ex method; no structure Compoundname RT min MH+ ¹H-NMR (DMSO-d₆) δ: 50

3-{4-[3-(3,5-difluoro- phenyl)-3-oxo-propenyl]- phenyl}-N-hydroxy-acrylamide A, 6.64 330.1 10.80 (s br, 2 H); 7.98 (d, 1 H); 7.97 (d, 2H); 7.93-7.84 (m, 2 H); 7.80 (d, 1 H); 7.66 (d, 2 H); 7.60 (ddd, 1 H);7.49 (d, 1 H); 6.58 (d, 1 H) 51

3-{4-[3-(2,5-difluoro- phenyl)-3-oxo-propenyl]- phenyl}-N-hydroxy-acrylamide A, 6.52 330.1 10.77 (s br, 1 H); 9.03 (s br, 1 H); 7.84 (d, 2H); 7.71-7.59 (m, 4 H); 7.57-7.41 (m, 4 H); 6.55 (d, 1 H) 52

3-{4-[3-(2,6-difluoro- phenyl)-3-oxo-propenyl]- phenyl}-N-hydroxy-acrylamide A, 6.45 330.1 10.80 (s br, 2 H); 7.82 (d, 2 H); 7.70-7.58 (m,3 H); 7.52 (d, 1 H); 7.47 (d, 1 H); 7.33-7.22 (m, 3 H); 6.56 (d, 1 H) 53

N-hydroxy-3-[3- methoxy-4-(3-oxo-3- thiophen-2-yl-propenyl)-phenyl]-acrylamide B, 5.97 330.2 10.73 (s br 1 H); 8.27 (d, 1 H); 8.06(d, 1 H); 8.01 (d, 1 H); 8.00 (d, 1 H); 7.85 (d, 1 H); 7.49 (d, 1 H);7.34-7.22 (m, 3 H); 6.60 (d, 1 H); 3.95 (s, 3 H) 54

N-hydroxy-3-[3- methyl-4-(3-oxo-3- thiophen-2-yl- propenyl)-phenyl]-acrylamide B, 5.97 314.2 10.75 (s br, 1 H); 8.33 (dd, 1 H); 8.07 (dd, 1H); 8.04 (d, 1 H); 7.94 (d, 1 H); 7.81 (d, 1 H); 7.53-7.39 (m, 3 H);7.32 (dd, 1 H); 6.54 (d, 1 H); 2.47 (s, 3 H) 55

4-{3-[4-(2-hydroxy- carbamoyl-vinyl)- phenyl]-acryloyl}- benzoic acidmethyl ester A, 6.5  352.1 10.77 (s, 1 H); 9.04 (s br, 1 H); 8.27 (d, 2H); 8.12 (d, 2 H); 7.97 (d, 1 H); 8.94 (d, 2 H); 7.78 (d, 1 H); 7.66 (d,2 H); 7.49 (d, 1 H); 6.57 (d, 1 H); 3.91 (s, 3 H) 56

3-{3-[4-(2-hydroxy- carbamoyl-vinyl)- phenyl]-acryloyl}- benzoic acidmethyl ester A, 6.78 352.1 8.60 (dd, 1 H); 8.46 (ddd, 1 H); 8.23 (ddd, 1H); 7.99 (d, 1 H); 7.95 (d, 2 H); 7.79 (d, 1 H); 7.75 (dd, 1 H); 7.65(d, 2 H); 7.49 (d, 1 H); 6.58 (d, 1 H); 3.92 (s, 3 H). 57

3-{4-[3-(5-chloro- thiophen-2-yl)-3-oxo- propenyl]-phenyl}-N-hydroxy-acrylamide A, 6.79 334.0 (1H DMSO): 10.78 (s, br, 1 H); 9.05 (s,br, 1 H); 8.27 (d, 1 H); 7.92 (d, 2 H); 7.89 (d, 1 H); 7.73 (d, 1 H);7.66 (d, 2 H); 7.49 (d, 1 H); 7.39 (d, 1 H); 6.56 (d, 1 H). 58

N-hydroxy-3-{4-[3-(3- hydroxy-phenyl)-3-oxo- propenyl]-phenyl}-acrylamide A, 5.85 310.1 (1H DMSO): 10.74 (s br, 1 H); 9.77 (s br, 1 H);7.95-7.83 (m, 3 H); 7.70 (d, 1 H); 7.63 (m, 3 H); 7.48 (d, 1 H); 7.45(dd, 1 H); 7.37 (dd, 1 H); 7.06 (dd, 1 H); 6.56 (d, 1 H). 59

N-hydroxy-3-(4-{3-[4- (4-methyl-piperazin-1- yl)-phenyl]-3-oxo-propenyl}-phenyl)- acrylamide A, 5.11 392.2 (1H DMSO): 10.78 (s, br, 1H); 10.53 (s br, 1 H); 9.04 (s, br, 1 H); 8.10 (d, 2 H); 7.95 (d, 1 H);7.91 (d, 2 H); 7.68 (d, # 1 H); 7.63 (d, 2 H); 7.48 (d, 1 H); 7.11 (d, 2H); 6.57 (d, 1 H); 4.13 (m, 2 H); 2.51 (m, 2 H); 3.33-3.04 (m, 4 H);2.83 (s br, 3 H).

Example 60N-hydroxy-3-[2-methoxy-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylamide

Step A

4-bromo-2-methoxybenzaldehyde (1 g, 4.67 mmol) was dissolved in MeOH (20ml) and trimethyl orthoformate (562 μl, 5.139 mmol) and p-toluenesulphonic acid monohydrate (89 mg, 0.467 mmol) were added to theresulting solution. The mixture was stirred overnight at roomtemperature and then the solvent was removed under vacuo. The residuewas taken up with Et₂O and washed with 5% Na₂CO₃ and with water. Theorganic phase was dried over Na₂SO₄ and evaporated to give 1.22 g of4-bromo-1-dimethoxymethyl-2-methoxy-benzene as a colorless oil.

Yield=99%

Step B

4-bromo-1-dimethoxymethyl-2-methoxy-benzene (1.22 g, 4.67 mmol) wasdissolved in dry THF (16 ml) and the resulting solution was cooled to−78° C. under N₂ atmosphere. n-BuLi in hexane (2.24 ml of a 2.5 Msolution) was added dropwise and the mixture was stirred at −78° C. for20 minutes and then treated with DMF (467 μl, 6.07 mmol) and stirred atroom temperature for 0.5 h.

The solution was partitioned between Et₂O and water and the organicextract was washed with water and brine then dried over Na₂SO₄ andevaporated under vacuo. 716 mg of4-dimethoxymethyl-3-methoxy-benzaldehyde were isolated by flash columnchromatography on sylica gel (EtOAc/petroleum ether 1:6).

Yield=72%

Step C

4-dimethoxymethyl-3-methoxy-benzaldehyde (716 mg, 3.41 mmol) wasdissolved in EtOH/H₂O (1:1, 20 ml) and to the resulting solution wereadded acetophenone (409 mg, 3.41 mmol) and 1.7 M KOH (3 ml).

The mixture was stirred for 5 h at room temperature, then diluted withEtOAc and washed twice with water. The organic phase was dried overNa₂SO₄ and evaporated under vacuo. The resulting oil was dissolved inTHF (10 ml) and treated with 1N HCl (10 ml). The solution was stirredfor 0.5 h at room temperature and then diluted with EtOAc and washedwith water. The organic phase was dried over Na₂SO₄ and concentratedunder vacuo. The resulting solid was triturated with EtOAc and filteredon a Buckner funnel giving 550 mg of2-methoxy-4-(3-oxo-3-phenyl-propenyl)-benzaldehyde as a yellow powder.

Yield=61%

Step D

2-methoxy-4-(3-oxo-3-phenyl-propenyl)-benzaldehyde (550 mg, 2.07 mmol)was dissolved in THF (5 ml) and the resulting solution was added to astirring mixture of tert-butyl diethylphosphonoacetate (603 mg, 2.27mmol) and NaH (107 mg, 2.69 mmol, 60% oil dispersion) in THF (5 ml).After 15 minutes the reaction was quenched by the addition of water andpartitioned between water and EtOAc. The organic extract was dried overNa₂SO₄ and evaporated under vacuo giving a crude that was purified bysilica gel chromatography (EtOAc/petroleum ether 1:6). The collectedfraction gave 635 mg of3-[2-methoxy-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylic acid tert-butylester as a yellow oil.

Yield=84%

Step E

3-[2-methoxy-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylic acid tert-butylester (635 mg, 1.74 mmol) was dissolved in DCM (12 ml) and TFA (3 ml)was added to the resulting solution. After stirring for 2 h at roomtemperature the solvent was removed under vacuo giving 541 mg of3-[2-methoxy-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylic acid as yellowpowder.

Yield=99%

Step F

3-[2-methoxy-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylic acid (200 mg,0.65 mmol) was dissolved in THF (6 ml) and HOBT (196 mg, 1.30 mmol), EDC(248 mg, 1.30 mmol), TEA (182 μl, 1.30 mmol) and NH₂OTHP (91 mg, 0.78mmol) were added to the resulting solution. The mixture was stirredovernight at room temperature and then partitioned between water andEtOAc. The organic extract was washed 3 times with water, dried overNa₂SO₄ and evaporated under vacuo.

The crude product was purified by silica gel chromatography(EtOAc/petroleum ether 1:1) and the resulting solid was dissolved in DCMand treated with HCl/Et₂O for 15 minutes. The precipitate was filteredon Buckner funnel giving 118 mg ofN-hydroxy-3-[2-methoxy-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylamide.

Yield=56%

LC-MS Method=A RT=7.42; (ES+) gave MH⁺: 324.1

¹H-NMR (DMSO-d₆,) δ: 8.16 (d, 2H); 7.98 (d, 1H); 7.74 (d, 1H); 7.68 (m,2H); 7.63-7.54 (m, 4H); 7.49 (d, 1H); 7.60 (d, 1H); 3.97 (s, 3H).

The compounds reported in Table 4 were prepared according to theprocedure described above TABLE 4 LC-MS Ex method; no structure Compoundname RT min MH+ ¹H-NMR (DMSO-d₆) δ: 61

3-[2-fluoro-4-(3-oxo-3- phenyl-propenyl)- phenyl]-N-hydroxy- acrylamideB, 6.20 312.1 10.87 (s br, 1 H); 9.07 (s br, 1 H); 8.18 (d, 2 H); 8.04(d, 1 H); 7.93 (d, 1 H); 7.78-7.65 (m, 4 H); 7.58 (m, 2 H); 7.52 (d, 1H); 6.66 (d, 1 H) 62

3-[2-chloro-4-(3-oxo-3- phenyl-propenyl)- phenyl]-N-hydroxy- acrylamideA, 6.62 328.1 8.18 (d, 2 H); 8.15 (d, 1 H); 8.05 (d, 1 H); 7.89 (dd, 1H); 7.78 (d, 1 H); 7.74 (d, 1 H); 7.71 (d, 1 H); 7.69 (dd, 1 H); 7.58(dd, 2 H); 6.63 (d, 1 H)

Example 63N-hydroxy-3-[4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylamide

Step A

4-bromo benzaldehyde (1 g, 5.40 mmol) was dissolved in MeOH (26 ml) and2M NaOH (5.4 ml). The resulting solution was cooled to 0° C. and3-acetyl-pyridine (592 μl, 5.40 mmol) was added dropwise. The mixturewas stirred for 1 h at 0° C. then the resulting solid was filtered andwashed with MeOH giving 832 mg of3-(4-bromo-phenyl)-1-pyridin-3-yl-propenone as a white powder.

Yield=53%

Step B

3-(4-bromo-phenyl)-1-pyridin-3-yl-propenone (823 mg, 2.87 mmol) wasdissolved in DMF (18 ml) and TEA (1.9 ml) and the resulting solution wasdegassed flushing N₂ for 20 min.

To the mixture were added NaHCO₃ (481 mg, 5.73 mmol), PPh₃ (37.5 mg,0.14 mmol), Pd(OAc)₂ (13 mg, 0.06 mmol), tert-butyl acrylate (420 μl,2.87 mmol) and the reaction was heated to 100° C. for 5 h. The resultingbrown solution was partitioned between water and Et₂O and the organicextract was washed with water, dried over Na₂SO₄ and evaporated undervacuo giving the crude product that was purified by silica gelchromatography (petroleum ether/EtOAc 1:1). The collected fraction gave680 mg of 3-[4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylic acidtert-butyl ester.

Yield=70%

Step C

3-[4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylic acid tert-butylester (680 mg, 2.03 mmol) was dissolved in DCM (15 ml) and TFA (5 ml).The resulting solution was stirred at room temperature for 4 h then thesolvent was removed under vacuo giving 600 mg of3-[4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylic acid as trifluoroacetate salt.

Yield=75%

Step D

3-[4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylic acid trifluoroacetate salt (550 mg, 1.4 mmol) was dissolved in THF/DMF (1:1, 20 ml)and to the resulting solution were added HOBT (536 mg, 3.94 mmol), EDC(752 mg, 3.94 mmol), TEA (822 μl, 3.94 mmol) and NH₂OTHP (276 mg, 2.36mmol). The mixture was stirred overnight at room temperature thenpartitioned between water and EtOAc. The organic extract was washed withwater and brine then dried over Na₂SO₄ and evaporated under vacuo.

The crude product was purified by silica gel chromatography (EtOAc) andthe resulting oil was dissolved in DCM and treated with HCl/Et₂O for 1h. The precipitate was filtered on Buckner funnel and was triturated inhot EtOH to give 380 mg ofN-hydroxy-3-[4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylamide ashydrochloric salt.

Yield=82%

LC-MS Method=B RT=4.99; (ES+) gave MH⁺: 295.1

¹H-NMR (DMSO-d₆,) δ: 9.43 (d, 1H); 8.93 (dd, 1H); 8.69 (ddd, 1H); 8.01(d, 1H); 7.96 (d, 2H); 7.82 (d, 1H); 7.81 (m, 1H); 7.67 (d, 2H); 7.49(d, 1H); 6.59 (d, 1H)

The compounds reported in Table 5 were prepared according to theprocedure described above TABLE 5 LC-MS Ex. method; no structureCompound name RT min MH+ ¹H-NMR (DMSO-d₆) δ: 64

N-hydroxy-3-[4-(3-oxo- 3-pyridin-2-yl-propenyl)- phenyl]-acrylamide A,5.76 295.1 8.81 (m, 1 H); 8.29 (d, 1 H); 8.12 (dd, 1 H); 8.07 (ddd, 1H); 7.87 (d, 2 H); 7.86 (d, 1 H); 7.71 (ddd, 1 H); 7.66 (d, 2 H); 6.48(d, 1 H); 6.56 (d, 1 H) 65

N-hydroxy-3-[4-(3-oxo- 3-pyridin-4-yl-propenyl)- phenyl]-acrylamide B,4.98 295.1 8.92 (m, 2 H); 8.12 (m, 2 H); 7.95 (d, 2 H); 7.92 (d, 1 H);7.80 (d, 1 H); 7.67 (d, 2 H); 7.49 (d, 1 H); 6.58 (d, 1 H) 66

N-hydroxy-3-[3-methyl- 4-(3-oxo-3-phenyl- propenyl)-phenyl]- acrylamideA, 5.34 308.1 10.74 (s br, 1 H); 9.06 (s br, 1 H); 8.16 (d, 2 H); 8.05(d, 1 H); 7.97 (d, 1 H); 7.86 (d, 1 H); 7.68 (dd, 1 H); 7.58 (dd, 2 H);7.47 (m, 2 H); 7.43 (d, 1 H); 7.54 (d, 1 H); 2.47 (s, 3 H) 67

N-hydroxy-3-[3- methoxy-4-(3-oxo-3- phenyl-propenyl)- phenyl]-acrylamideA, 6.47 324   10.75 (s br, 1 H); 9.07 (s br, 1 H); 8.12 (d, 2 H); 8.02(d, 1 H); 8.01 (d, 1 H); 7.90 (d, 1 H); 7.67 (dd, 1 H); 7.57 (dd, 2 H);7.49 (d, 1 H); 7.31 (s, 1 H); 7.25 (d, 1 H); 6.59 (d, 1 H); 3.95 (s, 3H)

Example 683-[3-fluoro-4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-N-hydroxacrylamide

Step A

4-bromo-2-fluoro benzaldehyde (988 mg, 4.86 mmol) and 3-acetyl-pyridine(533 μl, 4.86 mmol) were dissolved in EtOH (10 ml) and TEA (10.8 ml).The resulting solution was heated to reflux for 16 h then additionalamount of TEA (5 ml) was added. The mixture was heated to reflux for 16h then the solvent was removed under vacuo and the residue was taken upwith water and EtOAc. The organic extract was dried over Na₂SO₄ andevaporated. The resulting solid was triturated with isopropyl ether andfiltered on a buckner funnel to give 680 mg of3-(4-bromo-2-fluoro-phenyl)-1-pyridin-3-yl-propenone as a yellow powder.

Yield=45%

Step B

3-(4-bromo-phenyl)-1-pyridin-3-yl-propenone (668 mg, 2.18 mmol) weredissolved in DMF (11 ml) and TEA (1.3 ml) and the resulting solution wasdegassed flushing N₂ for 20 min.

To the mixture were added NaHCO₃ (366 mg, 4.37 mmol), PPh₃ (28.5 mg,0.11 mmol), Pd(OAc)₂ (10 mg, 0.044 mmol), tert-butyl acrylate (352 μl,2.40 mmol) and the reaction was heated to 100° C. for 5 h. The resultingbrown solution was partitioned between water and Et₂O and the organicextract was washed with water, dried over Na₂SO₄ and evaporated undervacuo giving the crude product that was purified on silica gelchromatography (petroleum ether/EtOAc 7:3). The collected fractions gave550 mg of 3-[3-fluoro-4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylicacid tert-butyl ester.

Yield=71%

Step C

3-[3-fFluoro-4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylic acidtert-butyl ester (550 mg, 1.55 mmol) was dissolved in DCM (15 ml) andTFA (5 ml). The resulting solution was stirred at RT for 4 h then thesolvent was removed under vacuo giving 636 mg of3-[3-fluoro-4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylic acid astrifluoro acetate salt.

Yield=quantitative

Step D

3-[3-fluoro-4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylic acidtrifluoro acetate salt (300 mg, 0.64 mmol) was dissolved in THF (5 ml)and DMF (2 ml). To the resulting solution HOBT (174 mg, 1.28 mmol), EDC(245 mg, 1.28 mmol), TEA (178 μl, 1.28 mmol) and NH₂OTHP (90 mg, 0.77mmol) were added. The mixture was stirred for 6 h at room temperatureand then partitioned between water and EtOAc. The organic extract waswashed with water, brine, dried over Na₂SO₄ and evaporated under vacuo.

The crude product was triturated in EtOAc, filtered on a Bucker funneland the resulting solid was dissolved in DCM and treated with HCl/Et₂Ofor 3 h. The precipitate was filtered giving 150 mg of3-[3-fluoro-4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-N-hydroxy-acrylamideas hydrochloric salt.

Yield=67%

LC-MS Method=A RT =−5.23; (ES+) gave MH⁺: 313.1

¹H-NMR (DMSO-d₆,) δ: 9.40 (d, 1H); 8.92 (dd, 1H); 8.63 (ddd, 1H); 8.20(dd, 1H); 8.05 (d, 1H); 7.87 (d, 1H); 7.77 (dd, 1H); 7.55 (m, 2H); 7.48(d, 1H); 6.63 (d, 1H).

Example 69N-hydroxy-3-[5-(3-oxo-3-phenyl-propenyl)-pyridin-2-yl]-acrylamide

Step A

Trimethyl orthoformate (643 μl, 5.9 mmol) and p-toluene sulphonic acidmonohydrate (102 mg, 0.54 mmol) were added to6-bromo-pyridine-3-carbaldehyde (1 g, 5.37 mmol) dissolved in MeOH (40ml). The mixture was stirred for 24 h at room temperature and thenpartitioned between water and Et₂O. The organic extract was washed withwater, 5% Na₂CO₃, dried over Na₂SO₄ and evaporated under vacuo to give1.2 g of 2-bromo-5-dimethoxymethyl-pyridine as a brown oil.

Yield=99%

Step B

2-bromo-5-dimethoxymethyl-pyridine (503 mg, 2.13 mmol) was dissolved indry THF (20 ml) and the resulting solution was cooled to −70° C. underN₂ atmosphere. 2.5 M Solution of n-BuLi in hexane (0.94 ml) was addeddropwise and the mixture was stirred at −70° C. for 15 minutes thentreated with DMF (245 μl, 3.19 mmol).

After 30 minutes the temperature was allowed to reach RT and the mixturewas partitioned between water and Et₂O. The organic extract was driedover Na₂SO₄ and evaporated under vacuo. The crude product was purifiedby chromatographic column (petroleum ether/EtOAc 7:3) to give 206 mg of5-dimethoxymethyl-pyridine-2-carbaldehyde.

Yield=44%

Step C

5-dimethoxymethyl-pyridine-2-carbaldehyde (355 mg, 1.97 mmol) wasdissolved in THF (10 ml), and the resulting solution was added to astirring mixture of tert-butyl diethylphosphonoacetate (547 mg, 2.169mmol) and NaH (102 mg, 2.56 mmol, 60% oil dispersion) in THF (5 ml).After 15 minutes the reaction was quenched by addition of water and theresulting slurry was extracted with Et₂O. The organic phase was driedover Na₂SO₄ and evaporated under vacuo. The crude product was purifiedby silica gel chromatography (petroleum ether/EtOAc 95:5) to give 491 mgof 3-(5-dimethoxymethyl-pyridin-2-yl)-acrylic acid tert-butyl ester.

Yield=89%

Step D

(491 mg, 1.76 mmol) of 3-(5-dimethoxymethyl-pyridin-2-yl)-acrylic acidtert-butyl ester was dissolved in THF (20 ml) and 1N HCl (7 ml).

The resulting solution was stirred for 4 h. Water (1 ml) and 10% HCl (1ml) were added. The mixture was stirred overnight then basified to pH=10with 20% NaOH and extracted with EtOAc. The organic phase was dried overNa₂SO₄ and evaporated under vacuo giving3-(5-formyl-pyridin-2-yl)-acrylic acid tert-butyl ester as a solid.

Yield=88%

Step E

3-(5-formyl-pyridin-2-yl)-acrylic acid tert-butyl ester (364 mg, 1.56mmol) was dissolved in MeOH (10 ml) and the solution was cooled to 0° C.Acetophenone (188 mg, 1.56 mmol) and 1.7M KOH (1.8 ml) were added. Thereaction was stirred at 0° C. for 3 h. The resulting solid was filteredon a Buckner funnel to give 130 mg of3-[5-(3-oxo-3-phenyl-propenyl)-pyridin-2-yl]-acrylic acid tert-butylester as a yellow powder.

Yield=25%

Step F

3-[5-(3-oxo-3-phenyl-propenyl)-pyridin-2-yl]-acrylic acid tert-butylester (130 mg, 0.38 mmol) was dissolved in DCM (4 ml) and TFA (1 ml).The resulting solution was stirred for 4 h at room temperature and thenthe solvent was removed under vacuo. The resulting oil was crystallizedfrom Et₂O to give 165 mg of3-[5-(3-oxo-3-phenyl-propenyl)-pyridin-2-yl]-acrylic acid as thetrifluoroacetate salt.

Yield=quantitative

Step G

HOBT (133 mg, 0.98 mmol), EDC (187 mg, 0.98 mmol), TEA (148 mg, 1.47mmol) and NH₂OTHP (68.8 mg, 0.59 mmol) were added to3-[5-(3-oxo-3-phenyl-propenyl)-pyridin-2-yl]-acrylic acidtrifluoroacetate salt (193 mg, 0.49 mmol) dissolved in THF/DMF (1:1, 10ml). The mixture was stirred for 6 h at room temperature and thenpartitioned between water and Et₂O. The organic extract was washed withbrine, dried over Na₂SO₄ and evaporated under vacuo.

The crude product was purified by silica gel chromatography (petroleumether/EtOAc 4:6) and the resulting oil was dissolved in DCM and treatedwith HCl/Et₂O for 1.5 h. The precipitate was filtered on a Bucknerfunnel washing with DCM and Et₂O to give 55 mg ofN-hydroxy-3-[5-(3-oxo-3-phenyl-propenyl)-pyridin-2-yl]-acrylamide ashydrochloric salt.

Yield=33%

LC-MS Method=B RT=5.58; (ES+) gave MH⁺: 295.2

¹H-NMR (DMSO-d₆,) δ: 9.06 (d, 1H); 8.45 (dd, 1H); 8.18 (d, 2H); 8.11 (d,1H); 7.78 (d, 1H); 7.76-7.66 (m, 2H); 7.59 (dd, 2H); 7.53 (d, 1H); 7.04(d, 1H)

The compounds reported in Table 6 were prepared according to theprocedure described above. TABLE 6 LC-MS Ex method; no structureCompound name RT min MH+ ¹H-NMR (DMSO-d₆) δ: 70

N-hydroxy-3-{5-[3-(2- methoxy-phenyl)-3-oxo- propenyl]-pyridin-2-yl}-acrylamide A, 5.71 325.2 8.93 (d, 1 H); 8.27 (dd, 1 H); 7.69 (d, 1 H);7.63-7.47 (m, 5 H); 7.21 (d, 1 H); 7.07 (ddd, 1 H); 7.01 (d, 1 H); 3.87(s, 3 H) 71

N-hydroxy-3-[5-(3-oxo- 3-thiophen-2-yl- propenyl)-pyridin-2-yl]-acrylamide A, 5.58 301.2 9.05 (d, 1 H); 8.40 (dd, 1 H); 8.35 (dd, 1 H);8.09 (dd, 1 H); 8.03 (d, 1 H); 7.77 (d, 1 H); 7.71 (d, 1 H); 7.51 (d, 1H); 7.34 (dd, 1 H); 7.02 (d, 1 H); 72

3-{5-[3-(3,4-difluoro- phenyl)-3-oxo-propenyl]- pyridin-2-yl}-N-hydroxy-acrylamide A, 5.33 331.1 10.90 (s br, 1 H); 9.04 (d, 1 H); 8.42 (dd, 1H); 8.26 (ddd, 1 H); 8.10 (d, 1 H); 8.10 (m, 1 H); 7.81 (d, 1 H); 7.70(d, 1 H); 7.66 (dd, 1 H); 7.52 (d, 1 H); 7.02 (d, 1 H).

2. Biochemistry and Pharmacology

Acetylation and deacetylation of nucleosomal histones play an importantrole in the modulation of chromatin structure, chromatin function and inthe regulation of gene expression. A number of structurally distinctclasses of compounds have been identified as HDAC inhibitors; thesecompounds lead to an accumulation of acetylated histone proteins both intumor cells and in normal tissues. HDAC inhibitors are able to activatedifferentiation, to arrest the cell cycle in G1 and/or G2, and to induceapoptosis in transformed or cancer cells.

Experiment Set 1

1. Histone Acetylation

U937 hematopoietic cell line was treated with several compounds in aconcentration interval comparable to that of tricostatin A, a compoundknown among the most powerful known inhibitors of histone deacetylases(micromolar concentrations). The levels of histone acetylation weremeasured by cytofluorimetry, using an antibody recognising H3 and H4acetylated histones. Similar results were obtained with a differenttechnique (western blotting) and in other cell lines.

As shown in FIG. 1, the tested compounds showed a strong inhibitoryactivity, with a spectrum of potency and inhibition stability (bycomparing data obtained after 4 h treatment) which correlates with thestability of the compounds and/or degree of inhibition of histonedeacetylases.

2. Cell Growth/Apoptosis/Cell Cycle.

The biological response of U937 cells to the compounds of formula (I)was studied. As a reference, a 24 hr treatment with tricostatin Ainduced strong apoptosis in U937 cells (approximately 60% of celldeath), together with a growing number of cells in G2/M phase, aspreviously described (Qiu et al., Mol. Biol. Cell., 2000, 11(6),2069-83).

Two compounds (MC1610 and MC1645) were studied at first: as shown inFIG. 2, both compounds (concentration 1 μM) interrupted cell growthcompletely, induced apoptosis and stimulated blockage in G2/M phase.

According to the aforementioned procedures, the present compounds werethus tested for their inhibiting activity towards HD2, HD1-B and HD1-A,which are mais enzymes with deacetylase activity. In particular HD1-Band HD1-A are homologues of class I and II mammalian deacetylasesrespectively. The obtained results are shown in table 7. TABLE 7

HD2, HD1-B, HD1-A, Compound Ar IC₅₀ nM IC₅₀ nM IC₅₀ nM MC1632 Ph 107 92108 MC1645 2-Cl-Ph  40 22  39 MC1622 3-Cl-Ph 118 91 120 MC1624 2-F-Ph 86 18  67 MC1610 3-F-Ph 144 85 117 MC1625 4-F-Ph  92 86 107 MC16442-Me-Ph  81 14  15 MC1623 3-Me-Ph 462 273  109 MC1639 4-Me-Ph 216 225 310 MC1652 1-naphtyl 202 57  14 MC1671 5-dihydrobenzofuran  51 28  15

HD2, HD1-B, HD1-A, Compound Ar IC₅₀ nM IC₅₀ nM IC₅₀ nM MC1646 Ph 32 2346 MC1670 2-Cl-Ph 65 29 40 MC1672 3-Cl-Ph 78 20 27 MC1661 2-F-Ph 38 1617 MC1653 3-F-Ph 135  50 33

Yield Compound (%) χ Mp ° C. MC1631 144 152 213

The data in table 7 show that all tested compounds have a powerfulinhibiting activity of histone deacetylases.

Experiment Set 2

Methods

In Vitro Studies

2.1 Histone Acetylation Assay

The histone acetylation assay is formatted for conventional detection ofrelative levels of acetylated histones in cell cultures. Suspensioncells (U937 or K562, respectively derived from a histiocytic lymphomaand a myelogenous leukemia) were exposed to increasing doses of HDACinhibitors (HDACi) to induce histone acetylation. After 3 h, cells werefixed (1% paraformaldehyde in PBS) and permeabilized (Triton X-100 0.1%in PBS, RT). After washing (PBS-1% BSA), cells were pre-incubated in 10%Goat Serum PBS (30′ at 4°). Cells were then incubated with a monoclonalantibody (in PBS-1% BSA; 1 hour RT) directed against acetylated histonesand then with an anti-mouse FITC conjugate antibody (in PBS-1% BSA; 1hour RT). After final washing, cells were FACS analysed.

2.2 HDAC Inhibition Assay

The HDAC activity assay was performed onto nuclear extract using an HDACfluorescent activity assay kit (Biomol Inc.), according tomanufacturer's recommendations. The assay was performed in two steps:first, 5 μg of HELA nuclear extract (HDAC activity) was added to asolution of HDAC inhibitor and substrate (acetylated lysine side chain,116 μM) and the mixture was then incubated for 10 min at roomtemperature (250). In the second step the reaction was stopped by theaddition of a developer (15 min at room temperature). In this step afluorophore was produced.

Fluorescence was analyzed using a Vector 3 fluorimeter (Perkin-Elmer)with a 355 nm excitation wavelength and detection of emitted light at460 nm.

2.3 MTT Assay

MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assayis based on the ability of a mitochondrial dehydrogenase enzyme fromviable cells to cleave the tetrazolium rings of the pale yellow MTT andform a dark blue formazan crystals which is largely impermeable to cellmembranes, thus resulting in its accumulation within healthy cells.Solubilisation of the cells by the addition of a detergent results inthe liberation of the crystals which are solubilized. The number ofsurviving cells is directly proportional to the level of the formazanproduct created. The color can then be quantified using a simplecolorimetric assay. The results can be read on a multiwell scanningspectrophotometer (ELISA reader).

Tumor cell lines (HT29, MCF-7, PC3, U937) were incubated (24, 48 and 72hour) with different concentrations of test compound. MTT (5 mg/ml inPBS) was added at different time points and incubated for 3-4 hours at37° C. After incubation, medium containing MTT solution was removed andformazan crystals were solubilised with an organic solvent (DMSO/Ethanolabsolute 1:1) before reading on scanning multiwell spectrophotometer(550-570 nm). The percentage of surviving cells is expressed as:(treated wells absorbance/control wells absorbance)×100

2.4 Cell Growth/Apoptosis/Cell Cycle

Suspension or adherent cells (HT29 or K562) were exposed to increasingdoses of HDACi compounds to evaluate their biological response. For cellcycle and apoptosis analysis cells, after collecting, were fixed in 70%ethanol for 30 min.

Following wash, cells were resuspended in Propidium Iodide (PI; 50 μg/mladditioned to RNase (250 μg/ml)) and incubated for 3 h at roomtemperature.

Samples were processed for flow cytometric (FC) analyses. FC wasperformed by FACScan Cytometer (Becton Dickinson). As shown in FIG. 3,the tested compounds were able to completely arrest cell growth, induceapoptosis and stimulate G0/G1 block.

In Vivo Studies

Antitumor Activity Studies

2.5 Carciginogenesis Study and HDACi Administration

Six-week-old female 129 mice were initially treated with 25 μg of DMBA(dissolved in 200 μl of acetone) painted onto the shaved back skin.Starting 2 weeks thereafter, mice were treated with 3 μg of TPA(dissolved in 200 μl of acetone) twice a week for the following 13weeks. Visible skin tumors (papillomas) were evident after six weeks ofTPA application. At the occurring of visible papillomas, HDACiadministration was initiated. HDAC inhibitors were dissolved inglycerol/H₂O/DMSO (7:2:1). HDACi were administered to groups of bothnormal or DMBA-TPA treated animals, one group being considered sham(only vehicle administration). HDACi (or vehicle) was painted onto theshaved back skin (2×3 cm). All groups were treated twice a week for thefollowing 6-7 weeks. All the visible tumors were counted weekly anddissected at the sacrifice (CO₂ inhalation) six weeks later.

2.6 Histological and Immunohistochemical Analysis

Tumors samples were fixed in 10% buffered formalin, processed forparaffin embedding and sectioned (4 μm). One series was stained withhematoxylin and eosin, while the others were immunohistochemicallyprocessed to detect levels of acetylated histones. In brief, afterde-paraffinization, tissue hydratation by graded alcohol series, andantigen unmasking in citrate solution (pH 6), sections were quenched (3%H₂O₂ in TBS) and incubated with anti-acetylated histones (in TBS 1×-BSA2%-NGS 2%-Tween 0.05%), for 2 hours at room temperature. Sections werethen incubated with ready to use secondary antibody (DAKO EnvisionSystem HRP anti mouse) for 1 hour at room temperature and subsequentlyincubated in peroxidase substrate solution (1 drop of chromogen in 1 mLof DAB DAKO buffer). Finally sections were washed in H₂O and dehydratefor mounting and observation.

Results

3.1 Histone Acetylation Assay and HDAC Inhibition Assay

According to the procedures mentioned in paragraphs 2.1 and 2.2, thepresent compounds were thus tested for their ability to inhibit histonedeacetylases. The obtained results are schematized in Table 8. TABLE 8Summary of the measured activity (HDAC Inhibition Assay and HistoneAcetylation Assay) Acetylation Activity compounds Activity incrementBiochem ASSAY MC1632 ++ +++ + MC1610 +++ ++ +++ MC1624 + + +++ Ex. 1 ++++ + Ex. 2 ++ ++ ++ Ex. 5 +++ ++ +++ Ex. 61 +++ +++ ++ Ex. 7 +++ + + Ex.9 +++ +++ + Ex. 22 ++ +++ ++ Ex. 24 +++ +++ nd Ex. 12 +++ ++ nd Ex. 30++ +++ nd Ex. 41 + ++ nd Ex. 43 + +++ nd Ex. 65 + +++ nd Ex. 63 + +++ ndEx. 45 ++ +++ ndIC50 range (nM):<100 = +++>100, <200 = ++>200, <600 = +Acetylation Increment range:<4 times = +>4 times, <6 times = ++>6 times = +++

The data shown in Table 8 demonstrate that the tested compounds possessa powerful inhibiting activity against histone deacetylases.

3.2 MTT Assay

In accordance with the procedure described in paragraphs 2.3, thepresent compounds were tested on different cell lines for their capacityto induce proliferation block and/or cell death. The obtained resultsare schematized in Table 9. TABLE 9 Activity MTT test compoundscompounds HT29 MCF7 PC3 U937 MC1632 ++ ++ ++ ++ MC1610 ++ ++ + ++ MC1624++ ++ + ++ Ex. 1 +++ ++ ++ ++ Ex. 2 +++ ++ ++ +++ Ex. 5 ++ ++ ++ ++ Ex.61 ++ ++ + ++ Ex. 7 +++ ++ ++ nd Ex. 9 +++ + ++ ++ Ex. 22 +++ ++ +++ ++Ex. 24 +++ ++ ++ nd Ex. 12 +++ ++ ++ nd Ex. 30 ++ ++ ++ nd Ex. 41 ++++ + nd Ex. 43 ++ ++ ++ nd Ex. 65 ++ ++ + nd Ex. 63 ++ ++ ++ nd Ex. 45+++ ++ +++ ndIC50 (μM) range:<0.5 = +++>0.5, <5 = ++>5 = +

The results shown in Table 9 indicate that the present compounds areable to induce proliferation block and/or cell death in a variety oftumor cell lines.

3.3 In Vivo Studies

In accordance with the procedures explained in paragraphs 2.5 and 2.6,cutis from normal mice or from mice exposed to DMBA-TPA treatment wasanalyzed by immunohistochemistry or stained with hematoxylin and eosin,respectively.

Examples of the obtained results are represented in FIG. 4 and FIG. 5which demonstrate that the tested compounds are able to strongly inducehistone acetylation in normal animals and are to able to reduce thetumor size in treated animals. Moreover, the tested compounds are ableto completely block the further number increase of induced papillomas asshown in FIG. 6.

1. A Compound of formula (I)

wherein: R₃ is chosen among hydrogen, alkoxyalkyl; Ar is an optionallysubstituted aryl or heteroaryl group. A is chosen among:

wherein R₂ is chosen among hydrogen, alkyl, cycloalkyl, aryl, arylalkyl,heterocyclyl, heterocyclylalkyl, halogen, haloalkyl, hydroxy,hydroxyalkyl, alkoxy, haloalkoxy, amino, aminoalkyl, alkylamino,(thio)carbonylamino, (thio)aminocarbonil, sulphonylamino,aminosulphonyl, (thio)acyl, (thio)acyloxy, (thio)alkoxycarbonyl, nitroand nitryl; R₁ is chosen among:

wherein Y represents O, S, NH, CH₂, NOH or NOR₅ where R₅ is an alkylhaving from 1 to 4 carbon atoms.
 2. The Compound according to claim 1,where Ar is chosen among phenyl, naphtyl, pyridyl, pyranyl, pyrrolyl,thienyl, furanyl, benzofuryl, benzothienyl, indolyl, optionallysubstituted.
 3. The Compound according to claim 1, where Ar issubstituted by one or more among halogen, hydroxy, alkyl, alkoxy,trifluoroalkyl, trifluoroalkoxy, dialkylamino, morpholyl, piperazinyl,metoxycarbonyl.
 4. The Compound according to claim 1 where the R₁ groupand the R₃-containing group are attached in para relationship to eachother on the A ring.
 5. The Compound according to claim 1, where R₂ ischosen among hydrogen, halogen, alkyl, alkoxy.
 6. The Compound accordingto claim 1, where R₃ is hydrogen.
 7. The Compound according to claim 1,having one of the following structures:

where Ar and R2 have the aforementioned meanings, and X is a carbon ornitrogen atom.
 8. The Compound according to claim 7, where in formulas(Ia-d) X is a carbon atom, R₂ is hydrogen, and Ar is chosen among:phenyl, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 2-fluorophenyl,3-fluorophenyl, 4-fluorophenyl, 2-methylphenyl, 3-methylphenyl,4-methylphenyl, 1-naphthyl, 5-dihydrobenzofuryl.
 9. The Compoundaccording to claim 1, chosen from:3-[3-fluoro-4-(3-oxo-3-phenyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-[3-chloro-4-(3-oxo-3-phenyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-[3-chloro-4-(3-oxo-3-o-tolyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(2-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(2-fluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(2-chloro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-[3-chloro-4-(3-oxo-3-m-tolyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(3-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(3-fluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(3-chloro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-[3-chloro-4-(3-oxo-3-p-tolyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(4-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(4-fluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-chloro-4-[3-(4-chloro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-[3-chloro-4-(3-oxo-3-thiophen-2-yl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-[3-fluoro-4-(3-oxo-3-o-tolyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-{3-fluoro-4-[3-(2-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-fluoro-4-[3-(2-fluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{4-[3-(2-chloro-phenyl)-3-oxo-propenyl]-3-fluoro-phenyl}-N-hydroxy-acrylamide;3-[3-fluoro-4-(3-oxo-3-m-tolyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-{3-fluoro-4-[3-(3-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-fluoro-4-[3-(3-fluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{4-[3-(3-chloro-phenyl)-3-oxo-propenyl]-3-fluoro-phenyl}-N-hydroxy-acrylamide;3-[3-fluoro-4-(3-oxo-3-p-tolyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-{3-fluoro-4-[3-(4-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{3-fluoro-4-[3-(4-fluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{4-[3-(4-chloro-phenyl)-3-oxo-propenyl]-3-fluoro-phenyl}-N-hydroxy-acrylamide;3-[3-fluoro-4-(3-oxo-3-thiophen-2-yl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-{3-fluoro-4-[3-(4-morpholin-4-yl-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;N-hydroxy-3-{4-[3-(2-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-acrylamide;N-hydroxy-3-{4-[3-oxo-3-(2-trifluoromethyl-phenyl)-propenyl]-phenyl}-acrylamide;N-hydroxy-3-{4-[3-oxo-3-(2-trifluoromethoxy-phenyl)-propenyl]-phenyl}-acrylamide;3-{4-[3-(2-bromo-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;N-hydroxy-3-{4-[3-(3-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-acrylamide;3-{4-[3-(3-bromo-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;N-hydroxy-3-{4-[3-(4-methoxy-phenyl)-3-oxo-propenyl]-phenyl}-acrylamide;N-hydroxy-3-{4-[3-oxo-3-(4-trifluoromethyl-phenyl)-propenyl]-phenyl}-acrylamide;N-hydroxy-3-{4-[3-oxo-3-(4-trifluoromethoxy-phenyl)-propenyl]-phenyl}-acrylamide;3-{4-[3-(4-bromo-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{4-[3-(4-diethylamino-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;N-hydroxy-3-{4-[3-(4-morpholin-4-yl-phenyl)-3-oxo-propenyl]-phenyl}-acrylamide;3-[4-(3-furan-2-yl-3-oxo-propenyl)-phenyl]-N-hydroxy-acrylamide;N-hydroxy-3-[4-(3-oxo-3-thiophen-2-yl-propenyl)-phenyl]-acrylamide;N-hydroxy-3-{4-[3-oxo-3-(1H-pyrrol-2-yl)-propenyl]-phenyl}-acrylamide;3-[4-(3-benzofuran-2-yl-3-oxo-propenyl)-phenyl]-N-hydroxy-acrylamide;3-[4-(3-benzo[b]thiophen-2-yl-3-oxo-propenyl)-phenyl]-N-hydroxy-acrylamide;N-hydroxy-3-[4-(3-oxo-3-thiophen-3-yl-propenyl)-phenyl]-acrylamide;N-hydroxy-3-{4-[3-(3-methoxy-4-morpholin-4-ylmethyl-phenyl)-3-oxo-propenyl]-phenyl}-acrylamide;3-{4-[3-(3,4-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{4-[3-(3,5-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{4-[3-(2,5-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;3-{4-[3-(2,6-difluoro-phenyl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;N-hydroxy-3-[3-methoxy-4-(3-oxo-3-thiophen-2-yl-propenyl)-phenyl]-acrylamide;N-hydroxy-3-[3-methyl-4-(3-oxo-3-thiophen-2-yl-propenyl)-phenyl]-acrylamide;4-{3-[4-(2-hydroxycarbamoyl-vinyl)-phenyl]-acryloyl}-benzoic acid methylester; 3-{3-[4-(2-hydroxycarbamoyl-vinyl)-phenyl]-acryloyl}-benzoic acidmethyl ester;3-{4-[3-(5-chloro-thiophen-2-yl)-3-oxo-propenyl]-phenyl}-N-hydroxy-acrylamide;N-hydroxy-3-{4-[3-(3-hydroxy-phenyl)-3-oxo-propenyl]-phenyl}-acrylamide;N-hydroxy-3-(4-{3-[4-(4-methyl-piperazin-1-yl)-phenyl]-3-oxo-propenyl}-phenyl)-acrylamide;N-hydroxy-3-[2-methoxy-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylamide;3-[2-fluoro-4-(3-oxo-3-phenyl-propenyl)-phenyl]-N-hydroxy-acrylamide;3-[2-chloro-4-(3-oxo-3-phenyl-propenyl)-phenyl]-N-hydroxy-acrylamide;N-hydroxy-3-[4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-acrylamide;N-hydroxy-3-[4-(3-oxo-3-pyridin-2-yl-propenyl)-phenyl]-acrylamide;N-hydroxy-3-[4-(3-oxo-3-pyridin-4-yl-propenyl)-phenyl]-acrylamide;N-hydroxy-3-[3-methyl-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylamide;N-hydroxy-3-[3-methoxy-4-(3-oxo-3-phenyl-propenyl)-phenyl]-acrylamide;3-[3-fluoro-4-(3-oxo-3-pyridin-3-yl-propenyl)-phenyl]-N-hydroxacrylamide;N-hydroxy-3-[5-(3-oxo-3-phenyl-propenyl)-pyridin-2-yl]-acrylamide;N-hydroxy-3-{5-[3-(2-methoxy-phenyl)-3-oxo-propenyl]-pyridin-2-yl}-acrylamide;N-hydroxy-3-[5-(3-oxo-3-thiophen-2-yl-propenyl)-pyridin-2-yl]-acrylamide.3-{5-[3-(3,4-difluoro-phenyl)-3-oxo-propenyl]-pyridin-2-yl}-N-hydroxy-acrylamide.10. A Process for preparation of the compounds of formula (I),comprising treating a compound of formula (II)

Where A and R₂ have the aforesaid meanings and R₄ is a suitable leavinggroup, (i) with a compound of formula Ar—W, where Ar has the aforesaidmeanings, and W is a group capable to form, by reaction with the CHOgroup of (II), the group R₁ as defined above, or a synthesisintermediate thereof (ii) and further with a compound of formula (III)

where Z represents NHOR₃ as defined above or a precursor thereof. 11.The Process according to claim 10, where the compound Ar—W is anacetophenone optionally substituted on the phenyl ring.
 12. The Processaccording to claim 10, where the addition reaction of compound Ar—Wtakes place in alkaline environment.
 13. The Process according to claim10, where the compound of formula (III) is an alkylacrylate.
 14. TheProcess according to claim 10, where the compound of formula (III) is an-butylacrylate.
 15. The Process according to claim 10, where theaddition reaction of the compound of formula (III) takes place inpresence of potassium phosphate and palladium acetate.
 16. The Compoundof formula (I) as defined in claim 1 for use in therapy.
 17. ThePharmaceutical composition wherein by comprising one or more activeprinciples of formula (I) as defined in claim 1, in association withpharmaceutically acceptable excipients and diluents.
 18. The Compositionaccording to claim 17, useful for oral or parenteral administration, inthe form of tablets, capsules, oral preparations, powders, granules,lozenges, regenerable powders, injectable or infusible liquid solutionsor suspensions, suppositories, aqueous or oily suspensions, solutions,emulsions, syrups, elixirs, or in the form of transdermal.
 19. TheComposition according to claim 17, useful for topical use in the form ofointment, cream, gel, lotion, solution, paste or the like, possiblycontaining liposomes, micelles, and/or microspheres.
 20. The method forthe prevention and/or treatment of diseases associated to thederegulation of the activity of histone deacetylases, comprisingadministering to a patient in need thereof, one or more compounds offormula (I) as defined in claim 1.